MSYS: Add support for running under MSYS runtime environment

Detect MSYS as CYGWIN, with the required adaptations.

60 files changed, 246 insertions, 66 deletions

diff --git a/Modules/CMakeDetermineSystem.cmake b/Modules/CMakeDetermineSystem.cmake
index c3f2b74..8c7af06 100644
--- a/Modules/CMakeDetermineSystem.cmake
+++ b/Modules/CMakeDetermineSystem.cmake
@@ -27,6 +27,7 @@
 # Tru64                         Tru64
 # Ultrix                        ULTRIX
 # cygwin                        CYGWIN_NT-5.1
+# MSYS                          MSYS_NT-6.1
 # MacOSX                        Darwin
 
 
@@ -43,7 +44,7 @@ if(CMAKE_HOST_UNIX)
     else()
       exec_program(${CMAKE_UNAME} ARGS -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION)
     endif()
-    if(CMAKE_HOST_SYSTEM_NAME MATCHES "Linux|CYGWIN.*|^GNU$|Android")
+    if(CMAKE_HOST_SYSTEM_NAME MATCHES "Linux|CYGWIN.*|MSYS.*|^GNU$|Android")
       exec_program(${CMAKE_UNAME} ARGS -m OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_PROCESSOR
         RETURN_VALUE val)
     elseif(CMAKE_HOST_SYSTEM_NAME MATCHES "Darwin")
diff --git a/Modules/CMakePlatformId.h.in b/Modules/CMakePlatformId.h.in
index 2643874..59195f8 100644
--- a/Modules/CMakePlatformId.h.in
+++ b/Modules/CMakePlatformId.h.in
@@ -5,6 +5,9 @@
 #if defined(__linux) || defined(__linux__) || defined(linux)
 # define PLATFORM_ID "Linux"
 
+#elif defined(__MSYS__)
+# define PLATFORM_ID "MSYS"
+
 #elif defined(__CYGWIN__)
 # define PLATFORM_ID "Cygwin"
 
diff --git a/Modules/CMakeSystemSpecificInformation.cmake b/Modules/CMakeSystemSpecificInformation.cmake
index ea3a445..0ded568 100644
--- a/Modules/CMakeSystemSpecificInformation.cmake
+++ b/Modules/CMakeSystemSpecificInformation.cmake
@@ -14,6 +14,7 @@
 set(APPLE  )
 set(UNIX   )
 set(CYGWIN )
+set(MSYS )
 set(WIN32  )
 
 
diff --git a/Modules/FindThreads.cmake b/Modules/FindThreads.cmake
index 28dffc0..c6a3451 100644
--- a/Modules/FindThreads.cmake
+++ b/Modules/FindThreads.cmake
@@ -225,7 +225,7 @@ if(CMAKE_USE_PTHREADS_INIT)
     set(CMAKE_THREAD_LIBS_INIT )
   endif()
 
-  if(CMAKE_SYSTEM MATCHES "CYGWIN_NT")
+  if(CMAKE_SYSTEM MATCHES "CYGWIN_NT" OR CMAKE_SYSTEM MATCHES "MSYS_NT")
     set(CMAKE_USE_PTHREADS_INIT 1)
     set(Threads_FOUND TRUE)
     set(CMAKE_THREAD_LIBS_INIT )
diff --git a/Modules/Platform/CYGWIN.cmake b/Modules/Platform/CYGWIN.cmake
index 9b897bd..fc4ea2e 100644
--- a/Modules/Platform/CYGWIN.cmake
+++ b/Modules/Platform/CYGWIN.cmake
@@ -1,7 +1,7 @@
-if("${CMAKE_MINIMUM_REQUIRED_VERSION}" VERSION_LESS "2.8.3.20101214")
+if("${CMAKE_MINIMUM_REQUIRED_VERSION}" VERSION_LESS "2.8.3.20101214" AND NOT MSYS)
   set(__USE_CMAKE_LEGACY_CYGWIN_WIN32 1)
 endif()
-if(NOT DEFINED WIN32)
+if(NOT DEFINED WIN32 AND NOT MSYS)
   set(WIN32 0)
   if(DEFINED __USE_CMAKE_LEGACY_CYGWIN_WIN32)
     if(NOT DEFINED CMAKE_LEGACY_CYGWIN_WIN32
diff --git a/Modules/Platform/MSYS-Clang-C.cmake b/Modules/Platform/MSYS-Clang-C.cmake
new file mode 100644
index 0000000..f025b33
--- /dev/null
+++ b/Modules/Platform/MSYS-Clang-C.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-Clang-C)
diff --git a/Modules/Platform/MSYS-Clang-CXX.cmake b/Modules/Platform/MSYS-Clang-CXX.cmake
new file mode 100644
index 0000000..e509eaa
--- /dev/null
+++ b/Modules/Platform/MSYS-Clang-CXX.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-Clang-CXX)
diff --git a/Modules/Platform/MSYS-Determine-CXX.cmake b/Modules/Platform/MSYS-Determine-CXX.cmake
new file mode 100644
index 0000000..dec17f0
--- /dev/null
+++ b/Modules/Platform/MSYS-Determine-CXX.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-Determine-CXX)
diff --git a/Modules/Platform/MSYS-GNU-C.cmake b/Modules/Platform/MSYS-GNU-C.cmake
new file mode 100644
index 0000000..e8343a4
--- /dev/null
+++ b/Modules/Platform/MSYS-GNU-C.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-GNU-C)
diff --git a/Modules/Platform/MSYS-GNU-CXX.cmake b/Modules/Platform/MSYS-GNU-CXX.cmake
new file mode 100644
index 0000000..67775de
--- /dev/null
+++ b/Modules/Platform/MSYS-GNU-CXX.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-GNU-CXX)
diff --git a/Modules/Platform/MSYS-GNU-Fortran.cmake b/Modules/Platform/MSYS-GNU-Fortran.cmake
new file mode 100644
index 0000000..b0b7d8e
--- /dev/null
+++ b/Modules/Platform/MSYS-GNU-Fortran.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-GNU-Fortran)
diff --git a/Modules/Platform/MSYS-GNU.cmake b/Modules/Platform/MSYS-GNU.cmake
new file mode 100644
index 0000000..012c112
--- /dev/null
+++ b/Modules/Platform/MSYS-GNU.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-GNU)
diff --git a/Modules/Platform/MSYS-windres.cmake b/Modules/Platform/MSYS-windres.cmake
new file mode 100644
index 0000000..faaccc2
--- /dev/null
+++ b/Modules/Platform/MSYS-windres.cmake
@@ -0,0 +1 @@
+include(Platform/CYGWIN-windres)
diff --git a/Modules/Platform/MSYS.cmake b/Modules/Platform/MSYS.cmake
new file mode 100644
index 0000000..96fa36f
--- /dev/null
+++ b/Modules/Platform/MSYS.cmake
@@ -0,0 +1,4 @@
+set(MSYS 1)
+include(Platform/CYGWIN)
+set(CMAKE_SHARED_LIBRARY_PREFIX "msys-")
+set(CMAKE_SHARED_MODULE_PREFIX "msys-")
diff --git a/Source/CMakeLists.txt b/Source/CMakeLists.txt
index 938745c..c19c154 100644
--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -44,7 +44,7 @@ endif()
 if(NOT CMake_DEFAULT_RECURSION_LIMIT)
   if(DEFINED ENV{DASHBOARD_TEST_FROM_CTEST})
     set(CMake_DEFAULT_RECURSION_LIMIT 100)
-  elseif(MINGW)
+  elseif(MINGW OR MSYS)
     set(CMake_DEFAULT_RECURSION_LIMIT 400)
   elseif(WIN32 AND CMAKE_C_COMPILER_ID STREQUAL "IntelLLVM")
     set(CMake_DEFAULT_RECURSION_LIMIT 600)
diff --git a/Source/Checks/cm_cxx_features.cmake b/Source/Checks/cm_cxx_features.cmake
index 7917d41..f20572e 100644
--- a/Source/Checks/cm_cxx_features.cmake
+++ b/Source/Checks/cm_cxx_features.cmake
@@ -80,7 +80,9 @@ if(CMake_HAVE_CXX_MAKE_UNIQUE)
   set(CMake_HAVE_CXX_UNIQUE_PTR 1)
 endif()
 cm_check_cxx_feature(unique_ptr)
-if (NOT CMAKE_CXX_STANDARD LESS "17")
+if (NOT CMAKE_CXX_STANDARD LESS "17"
+    AND NOT MSYS # FIXME: RunCMake.cmake_path cases crash with MSYS std::filesystem
+    )
   if (NOT CMAKE_CROSSCOMPILING OR CMAKE_CROSSCOMPILING_EMULATOR)
     cm_check_cxx_feature(filesystem TRY_RUN)
   else()
diff --git a/Source/Modules/FindLibUUID.cmake b/Source/Modules/FindLibUUID.cmake
index 17f11c1..ca5b61d 100644
--- a/Source/Modules/FindLibUUID.cmake
+++ b/Source/Modules/FindLibUUID.cmake
@@ -40,7 +40,14 @@ They may be set by end users to point at LibUUID components.
 #]=======================================================================]
 
 #-----------------------------------------------------------------------------
-if(CYGWIN)
+if(MSYS)
+  # Note: on current version of MSYS2, linking to libuuid.dll.a doesn't
+  #       import the right symbols sometimes. Fix this by linking directly
+  #       to the DLL that provides the symbols, instead.
+  find_library(LibUUID_LIBRARY
+    NAMES msys-uuid-1.dll
+    )
+elseif(CYGWIN)
   # Note: on current version of Cygwin, linking to libuuid.dll.a doesn't
   #       import the right symbols sometimes. Fix this by linking directly
   #       to the DLL that provides the symbols, instead.
diff --git a/Source/cmExtraEclipseCDT4Generator.cxx b/Source/cmExtraEclipseCDT4Generator.cxx
index ccfd727..5fbbef7 100644
--- a/Source/cmExtraEclipseCDT4Generator.cxx
+++ b/Source/cmExtraEclipseCDT4Generator.cxx
@@ -655,7 +655,7 @@ void cmExtraEclipseCDT4Generator::CreateCProjectFile() const
     xml.EndElement(); // extension
   } else {
     std::string systemName = mf->GetSafeDefinition("CMAKE_SYSTEM_NAME");
-    if (systemName == "CYGWIN") {
+    if (systemName == "CYGWIN" || systemName == "MSYS") {
       xml.StartElement("extension");
       xml.Attribute("id", "org.eclipse.cdt.core.Cygwin_PE");
       xml.Attribute("point", "org.eclipse.cdt.core.BinaryParser");
diff --git a/Source/cmSystemTools.cxx b/Source/cmSystemTools.cxx
index 5382fac..aad5533 100644
--- a/Source/cmSystemTools.cxx
+++ b/Source/cmSystemTools.cxx
@@ -3239,10 +3239,14 @@ cm::string_view cmSystemTools::GetSystemName()
       systemName = "kFreeBSD";
     }
 
-    // fix for CYGWIN which has windows version in it
+    // fix for CYGWIN and MSYS which have windows version in them
     if (systemName.find("CYGWIN") != cm::string_view::npos) {
       systemName = "CYGWIN";
     }
+
+    if (systemName.find("MSYS") != cm::string_view::npos) {
+      systemName = "MSYS";
+    }
     return systemName;
   }
   return "";
diff --git a/Tests/CMakeLists.txt b/Tests/CMakeLists.txt
index d6a20bc..ff9e9ec 100644
--- a/Tests/CMakeLists.txt
+++ b/Tests/CMakeLists.txt
@@ -460,7 +460,7 @@ if(BUILD_TESTING)
   ADD_TEST_MACRO(OutName exe.OutName.exe)
   ADD_TEST_MACRO(ObjectLibrary UseCshared)
   ADD_TEST_MACRO(NewlineArgs NewlineArgs)
-  ADD_TEST_MACRO(SetLang SetLang)
+  ADD_TEST_MACRO(SetLang SetLangX)
   ADD_TEST_MACRO(EmptyProperty EmptyProperty)
   ADD_TEST_MACRO(ExternalOBJ ExternalOBJ)
   if(NOT CMake_TEST_EXTERNAL_CMAKE)
diff --git a/Tests/CMakeOnly/CheckCXXCompilerFlag/CMakeLists.txt b/Tests/CMakeOnly/CheckCXXCompilerFlag/CMakeLists.txt
index 7ca68ec..aca99ce 100644
--- a/Tests/CMakeOnly/CheckCXXCompilerFlag/CMakeLists.txt
+++ b/Tests/CMakeOnly/CheckCXXCompilerFlag/CMakeLists.txt
@@ -36,7 +36,7 @@ if(CMAKE_CXX_COMPILER_ID MATCHES Intel)
   string (REGEX REPLACE ".*Version ([0-9]+(\\.[0-9]+)+).*" "\\1" _intel_version "${_intel_version_info}")
 endif()
 
-message("Platform:\n  WIN32: ${WIN32}\n  UNIX: ${UNIX}\n  APPLE: ${APPLE}\n  MINGW: ${MINGW}\n  CYGWIN: ${CYGWIN}\n"
+message("Platform:\n  WIN32: ${WIN32}\n  UNIX: ${UNIX}\n  APPLE: ${APPLE}\n  MINGW: ${MINGW}\n  CYGWIN: ${CYGWIN}\n  MSYS: ${MSYS}\n"
   "  MSVC: ${MSVC}\n  MSVC60: ${MSVC60}\n  MSVC70: ${MSVC70}\n  MSVC71: ${MSVC71}\n  MSVC80: ${MSVC80}\n  MSVC90: ${MSVC90}\n  MSVC10: ${MSVC10}\n"
   "  GCC: ${_gcc_version}\n"
   "  Clang: ${_clang_version}\n"
diff --git a/Tests/CMakeTests/ImplicitLinkInfoTest.cmake.in b/Tests/CMakeTests/ImplicitLinkInfoTest.cmake.in
index f01e616..1254ff9 100644
--- a/Tests/CMakeTests/ImplicitLinkInfoTest.cmake.in
+++ b/Tests/CMakeTests/ImplicitLinkInfoTest.cmake.in
@@ -459,7 +459,28 @@ set(msys_g77_dirs "C:/some-mingw/lib/gcc/mingw32/3.4.5;C:/some-mingw/lib/gcc;/so
 list(APPEND platforms msys_g77)
 
 #-----------------------------------------------------------------------------
-# MSYS2
+# MSYS2-runtime
+
+# gcc dummy.c -v
+set(msys2rt_gcc_text " /usr/lib/gcc/i686-pc-msys/6.4.0/collect2.exe -Bdynamic --dll-search-prefix=msys- /usr/lib/gcc/i686-pc-msys/6.4.0/../../../crt0.o -L/usr/lib/gcc/i686-pc-msys/6.4.0 -L/usr/lib/gcc/i686-pc-msys/6.4.0 -L/usr/lib/gcc/i686-pc-msys/6.4.0/../../.. /home/user/AppData/Local/Temp/cczg1Arh.o -lgcc -lmsys-2.0 -luser32 -lkernel32 -ladvapi32 -lshell32 -lgcc")
+set(msys2rt_gcc_libs "msys-2.0;user32;kernel32;advapi32;shell32")
+set(msys2rt_gcc_dirs "/usr/lib/gcc/i686-pc-msys/6.4.0;/usr/lib")
+list(APPEND platforms msysrt_gcc)
+
+# g++ dummy.cxx -v
+set(msys2rt_g++_text " /usr/lib/gcc/i686-pc-msys/6.4.0/collect2.exe -Bdynamic --dll-search-prefix=msys- /usr/lib/gcc/i686-pc-msys/6.4.0/../../../crt0.o -L/usr/lib/gcc/i686-pc-msys/6.4.0 -L/usr/lib/gcc/i686-pc-msys/6.4.0 -L/usr/lib/gcc/i686-pc-msys/6.4.0/../../.. /home/user/AppData/Local/Temp/ccsvcDO6.o -lstdc++ -lgcc -lmsys-2.0 -luser32 -lkernel32 -ladvapi32 -lshell32 -lgcc")
+set(msys2rt_g++_libs "stdc++;msys-2.0;user32;kernel32;advapi32;shell32")
+set(msys2rt_g++_dirs "/usr/lib/gcc/i686-pc-msys/6.4.0;/usr/lib")
+list(APPEND platforms msysrt_g++)
+
+# g77 dummy.f -v
+set(msys2rt_g77_text "Configured with: ... LD=/opt/gcc-tools/bin/ld.exe /usr/lib/gcc/i686-pc-msys/6.4.0/collect2.exe -Bdynamic --dll-search-prefix=msys- -u ___register_frame_info -u ___deregister_frame_info /usr/lib/gcc/i686-pc-msys/6.4.0/../../../crt0.o /usr/lib/gcc/i686-pc-msys/6.4.0/crtbegin.o -L/usr/lib/gcc/i686-pc-msys/6.4.0 -L/usr/lib/gcc/i686-pc-msys/6.4.0 -L/usr/lib/gcc/i686-pc-msys/6.4.0/../../.. /home/user/AppData/Local/Temp/ccqRWKWg.o -lgfortranbegin -lgfortran -lgcc_s -lgcc_s -lgcc -lmsys-2.0 -luser32 -lkernel32 -ladvapi32 -lshell32 -lgcc_s -lgcc_s -lgcc /usr/lib/gcc/i686-pc-msys/6.4.0/crtend.o")
+set(msys2rt_g77_libs "stdc++;msys-2.0;user32;kernel32;advapi32;shell32")
+set(msys2rt_g77_dirs "/usr/lib/gcc/i686-pc-msys/6.4.0;/usr/lib")
+list(APPEND platforms msysrt_g77)
+
+#-----------------------------------------------------------------------------
+# MSYS2-mingw
 
 # gcc dummy.c -v
 set(msys2_gcc_text " C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/collect2.exe -plugin C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/liblto_plugin-0.dll -plugin-opt=C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/lto-wrapper.exe -plugin-opt=-fresolution=C:/msys64/tmp/ccikz9Wf.res -plugin-opt=-pass-through=-lmingw32 -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_eh -plugin-opt=-pass-through=-lmoldname -plugin-opt=-pass-through=-lmingwex -plugin-opt=-pass-through=-lmsvcrt -plugin-opt=-pass-through=-lpthread -plugin-opt=-pass-through=-ladvapi32 -plugin-opt=-pass-through=-lshell32 -plugin-opt=-pass-through=-luser32 -plugin-opt=-pass-through=-lkernel32 -plugin-opt=-pass-through=-lmingw32 -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_eh -plugin-opt=-pass-through=-lmoldname -plugin-opt=-pass-through=-lmingwex -plugin-opt=-pass-through=-lmsvcrt -m i386pep -Bdynamic C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../../../x86_64-w64-mingw32/lib/../lib/crt2.o C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/crtbegin.o -LC:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0 -LC:/msys64/mingw64/bin/../lib/gcc -LC:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../../../x86_64-w64-mingw32/lib/../lib -LC:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../../../lib -LC:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../../../x86_64-w64-mingw32/lib -LC:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../.. C:/msys64/tmp/ccK0dTUv.o -lmingw32 -lgcc -lgcc_eh -lmoldname -lmingwex -lmsvcrt -lpthread -ladvapi32 -lshell32 -luser32 -lkernel32 -lmingw32 -lgcc -lgcc_eh -lmoldname -lmingwex -lmsvcrt C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/../../../../x86_64-w64-mingw32/lib/../lib/default-manifest.o C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/7.2.0/crtend.o")
diff --git a/Tests/FindPackageTest/CMakeLists.txt b/Tests/FindPackageTest/CMakeLists.txt
index 7217f43..7ec41f3 100644
--- a/Tests/FindPackageTest/CMakeLists.txt
+++ b/Tests/FindPackageTest/CMakeLists.txt
@@ -189,7 +189,9 @@ find_package(ArchD 4.0 EXACT NAMES zot)
 unset(CMAKE_LIBRARY_ARCHITECTURE)
 
 # Test find_package() with CMAKE_FIND_PACKAGE_RESOLVE_SYMLINKS enabled
-if(UNIX)
+if(UNIX
+    AND NOT MSYS # FIXME: This works on CYGWIN but not on MSYS
+    )
   # Create ./symlink pointing back here.
   execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink
       . "${CMAKE_CURRENT_SOURCE_DIR}/symlink")
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 5e16de0..db90a81 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -165,7 +165,7 @@ if(CMAKE_GENERATOR MATCHES "Ninja")
   endif()
   add_RunCMake_test(Ninja)
   set(NinjaMultiConfig_ARGS
-    -DCYGWIN=${CYGWIN}
+    -DCYGWIN=${CYGWIN} -DMSYS=${MSYS}
     )
   if(CMake_TEST_Qt5 AND Qt5Core_FOUND)
     list(APPEND NinjaMultiConfig_ARGS -DCMake_TEST_Qt5=1 -DQt5Core_DIR=${Qt5Core_DIR} -DCMAKE_TEST_Qt5Core_Version=${Qt5Core_VERSION})
@@ -346,7 +346,7 @@ add_RunCMake_test(export)
 add_RunCMake_test(cmake_language)
 add_RunCMake_test(cmake_minimum_required)
 add_RunCMake_test(cmake_parse_arguments)
-add_RunCMake_test(cmake_path)
+add_RunCMake_test(cmake_path -DMSYS=${MSYS})
 add_RunCMake_test(continue)
 add_executable(color_warning color_warning.c)
 add_executable(fake_build_command fake_build_command.c)
@@ -367,14 +367,14 @@ add_RunCMake_test(ctest_skipped_test)
 add_RunCMake_test(ctest_update)
 add_RunCMake_test(ctest_upload)
 add_RunCMake_test(ctest_fixtures)
-add_RunCMake_test(file)
-add_RunCMake_test(file-CHMOD)
+add_RunCMake_test(file -DMSYS=${MSYS})
+add_RunCMake_test(file-CHMOD -DMSYS=${MSYS})
 if(HAVE_ELF_H OR CMAKE_SYSTEM_NAME STREQUAL "AIX")
   add_RunCMake_test(file-RPATH -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME} -DHAVE_ELF_H=${HAVE_ELF_H})
 endif()
 add_RunCMake_test(find_file)
-add_RunCMake_test(find_library -DCYGWIN=${CYGWIN})
-add_RunCMake_test(find_package)
+add_RunCMake_test(find_library -DCYGWIN=${CYGWIN} -DMSYS=${MSYS})
+add_RunCMake_test(find_package -DMSYS=${MSYS})
 add_RunCMake_test(find_path)
 add_RunCMake_test(find_program -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME})
 add_RunCMake_test(foreach)
@@ -512,7 +512,9 @@ else()
   message(STATUS "Could not find ctresalloc")
 endif()
 
-if(NOT WIN32)
+if(NOT WIN32
+    AND NOT MSYS # FIXME: This works on CYGWIN but not on MSYS
+    )
   add_RunCMake_test(SymlinkTrees)
 endif ()
 
@@ -616,7 +618,8 @@ endif()
 
 
 add_executable(pseudo_llvm-rc pseudo_llvm-rc.c)
-add_RunCMake_test(CommandLine -DLLVM_RC=$<TARGET_FILE:pseudo_llvm-rc> -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME} -DCYGWIN=${CYGWIN} -DPYTHON_EXECUTABLE=${PYTHON_EXECUTABLE})
+add_RunCMake_test(CommandLine -DLLVM_RC=$<TARGET_FILE:pseudo_llvm-rc> -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}
+                  -DCYGWIN=${CYGWIN} -DMSYS=${MSYS} -DPYTHON_EXECUTABLE=${PYTHON_EXECUTABLE})
 add_RunCMake_test(CommandLineTar)
 
 if(CMAKE_PLATFORM_NO_VERSIONED_SONAME OR (NOT CMAKE_SHARED_LIBRARY_SONAME_FLAG AND NOT CMAKE_SHARED_LIBRARY_SONAME_C_FLAG))
@@ -625,7 +628,7 @@ else()
   set(NO_NAMELINK 0)
 endif()
 
-add_RunCMake_test(install -DNO_NAMELINK=${NO_NAMELINK} -DCYGWIN=${CYGWIN}
+add_RunCMake_test(install -DNO_NAMELINK=${NO_NAMELINK} -DCYGWIN=${CYGWIN} -DMSYS=${MSYS}
   -DCMAKE_SHARED_LIBRARY_RPATH_ORIGIN_TOKEN=${CMAKE_SHARED_LIBRARY_RPATH_ORIGIN_TOKEN}
   -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}
   -DCMAKE_SHARED_LIBRARY_RUNTIME_C_FLAG=${CMAKE_SHARED_LIBRARY_RUNTIME_C_FLAG}
diff --git a/Tests/RunCMake/CommandLine/RunCMakeTest.cmake b/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
index bf5a96e..78c3508 100644
--- a/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
+++ b/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
@@ -562,7 +562,7 @@ file(MAKE_DIRECTORY ${out})
 run_cmake_command(E_cat_non_existing_file
   ${CMAKE_COMMAND} -E cat ${out}/non-existing-file.txt)
 
-if(UNIX)
+if(UNIX AND NOT MSYS)
   # test non readable file only if not root
   execute_process(
     COMMAND id -u $ENV{USER}
@@ -801,7 +801,7 @@ function(reject_fifo)
     run_cmake_command(reject_fifo ${BASH_EXECUTABLE} -c ${BASH_COMMAND_ARGUMENT})
   endif()
 endfunction()
-if(CMAKE_HOST_UNIX AND NOT CMAKE_SYSTEM_NAME STREQUAL "CYGWIN")
+if(CMAKE_HOST_UNIX AND NOT CMAKE_SYSTEM_NAME STREQUAL "CYGWIN" AND NOT CMAKE_SYSTEM_NAME STREQUAL "MSYS")
   reject_fifo()
   run_cmake_command(closed_stdin  sh -c "\"${CMAKE_COMMAND}\" --version <&-")
   run_cmake_command(closed_stdout sh -c "\"${CMAKE_COMMAND}\" --version >&-")
diff --git a/Tests/RunCMake/FileAPI/codemodel-v2-data/directories/top.json b/Tests/RunCMake/FileAPI/codemodel-v2-data/directories/top.json
index ce45947..4727607 100644
--- a/Tests/RunCMake/FileAPI/codemodel-v2-data/directories/top.json
+++ b/Tests/RunCMake/FileAPI/codemodel-v2-data/directories/top.json
@@ -119,7 +119,7 @@
             "type": "target",
             "destination": "lib",
             "paths": [
-                "^lib/((Debug|Release|MinSizeRel|RelWithDebInfo)/)?(lib|cyg)?c_shared_lib(-1)?\\.(dll|so)$"
+                "^lib/((Debug|Release|MinSizeRel|RelWithDebInfo)/)?(lib|cyg|msys-)?c_shared_lib(-1)?\\.(dll|so)$"
             ],
             "pathsNamelink": [
                 "^lib/((Debug|Release|MinSizeRel|RelWithDebInfo)/)?(lib)?c_shared_lib\\.(so\\.1\\.2\\.3|1\\.2\\.3\\.dylib)$",
@@ -210,7 +210,7 @@
             "type": "target",
             "destination": "lib",
             "paths": [
-                "^cxx/((Debug|Release|MinSizeRel|RelWithDebInfo)/)?(lib|cyg)?cxx_shared_lib\\.(dll|so|dylib)$"
+                "^cxx/((Debug|Release|MinSizeRel|RelWithDebInfo)/)?(lib|cyg|msys-)?cxx_shared_lib\\.(dll|so|dylib)$"
             ],
             "isExcludeFromAll": null,
             "isOptional": null,
diff --git a/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/c_shared_lib.json b/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/c_shared_lib.json
index 5588bd5..e3a8d0b 100644
--- a/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/c_shared_lib.json
+++ b/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/c_shared_lib.json
@@ -90,10 +90,10 @@
         }
     ],
     "folder": null,
-    "nameOnDisk": "^(lib|cyg)?c_shared_lib(-1)?\\.(so|dylib|dll)$",
+    "nameOnDisk": "^(lib|cyg|msys-)?c_shared_lib(-1)?\\.(so|dylib|dll)$",
     "artifacts": [
         {
-            "path": "^lib/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg)?c_shared_lib(-1)?\\.(so|dylib|dll)$",
+            "path": "^lib/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg|msys-)?c_shared_lib(-1)?\\.(so|dylib|dll)$",
             "_dllExtra": false
         },
         {
@@ -101,7 +101,7 @@
             "_dllExtra": true
         },
         {
-            "path": "^lib/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg)?c_shared_lib(-1)?\\.pdb$",
+            "path": "^lib/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg|msys-)?c_shared_lib(-1)?\\.pdb$",
             "_dllExtra": true
         }
     ],
diff --git a/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/cxx_shared_lib.json b/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/cxx_shared_lib.json
index e5e1d0d..73e8e12 100644
--- a/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/cxx_shared_lib.json
+++ b/Tests/RunCMake/FileAPI/codemodel-v2-data/targets/cxx_shared_lib.json
@@ -66,10 +66,10 @@
         }
     ],
     "folder": null,
-    "nameOnDisk": "^(lib|cyg)?cxx_shared_lib\\.(so|dylib|dll)$",
+    "nameOnDisk": "^(lib|cyg|msys-)?cxx_shared_lib\\.(so|dylib|dll)$",
     "artifacts": [
         {
-            "path": "^cxx/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg)?cxx_shared_lib\\.(so|dylib|dll)$",
+            "path": "^cxx/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg|msys-)?cxx_shared_lib\\.(so|dylib|dll)$",
             "_dllExtra": false
         },
         {
@@ -77,7 +77,7 @@
             "_dllExtra": true
         },
         {
-            "path": "^cxx/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg)?cxx_shared_lib\\.pdb$",
+            "path": "^cxx/((Debug|Release|RelWithDebInfo|MinSizeRel)/)?(lib|cyg|msys-)?cxx_shared_lib\\.pdb$",
             "_dllExtra": true
         }
     ],
diff --git a/Tests/RunCMake/File_Generate/CustomFilePermissions.cmake b/Tests/RunCMake/File_Generate/CustomFilePermissions.cmake
index 0000ef9..a5e66dc 100644
--- a/Tests/RunCMake/File_Generate/CustomFilePermissions.cmake
+++ b/Tests/RunCMake/File_Generate/CustomFilePermissions.cmake
@@ -11,5 +11,6 @@ file(GENERATE OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/$<LOWER_CASE:$<CONFIG>>/custom
 add_custom_target(checkCustomFilePermissions ALL
   COMMAND ${CMAKE_COMMAND}
     -DgeneratedFile=${CMAKE_CURRENT_BINARY_DIR}/$<LOWER_CASE:$<CONFIG>>/customfilepermissions.txt
+    -DMSYS=${MSYS}
     -P "${CMAKE_CURRENT_SOURCE_DIR}/CustomFilePermissionsVerify.cmake"
   )
diff --git a/Tests/RunCMake/File_Generate/CustomFilePermissionsVerify.cmake b/Tests/RunCMake/File_Generate/CustomFilePermissionsVerify.cmake
index a87e916..2ef3281 100644
--- a/Tests/RunCMake/File_Generate/CustomFilePermissionsVerify.cmake
+++ b/Tests/RunCMake/File_Generate/CustomFilePermissionsVerify.cmake
@@ -2,7 +2,7 @@ if(NOT EXISTS "${generatedFile}")
   message(SEND_ERROR "Missing file:\n  ${generatedFile}")
 endif()
 
-if (UNIX)
+if (UNIX AND NOT MSYS)
   find_program(STAT_EXECUTABLE NAMES stat)
   if(NOT STAT_EXECUTABLE)
     return()
diff --git a/Tests/RunCMake/File_Generate/NoSourcePermissionsVerify.cmake b/Tests/RunCMake/File_Generate/NoSourcePermissionsVerify.cmake
index 7981ccc..5e5b16a 100644
--- a/Tests/RunCMake/File_Generate/NoSourcePermissionsVerify.cmake
+++ b/Tests/RunCMake/File_Generate/NoSourcePermissionsVerify.cmake
@@ -2,7 +2,7 @@ if(NOT EXISTS "${generatedFile}")
   message(SEND_ERROR "Missing generated file:\n  ${generatedFile}")
 endif()
 
-if (UNIX)
+if (UNIX AND NOT MSYS)
   find_program(STAT_EXECUTABLE NAMES stat)
   if(NOT STAT_EXECUTABLE)
     return()
diff --git a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME-imported-target.cmake b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME-imported-target.cmake
index 40f7c66..7eec527 100644
--- a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME-imported-target.cmake
+++ b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME-imported-target.cmake
@@ -58,8 +58,8 @@ set_property (TARGET static3 PROPERTY ARCHIVE_OUTPUT_NAME static3_archive)
 string (APPEND GENERATE_CONTENT [[
 
 check_value ("TARGET_FILE_BASE_NAME executable all properties" "$<TARGET_FILE_BASE_NAME:exec3>" "exec3_runtime")
-check_value ("TARGET_FILE_BASE_NAME shared all properties" "$<TARGET_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared3_runtime,shared3_library>")
-check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties" "$<TARGET_LINKER_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared3_archive,shared3_library>")
+check_value ("TARGET_FILE_BASE_NAME shared all properties" "$<TARGET_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared3_runtime,shared3_library>")
+check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties" "$<TARGET_LINKER_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared3_archive,shared3_library>")
 check_value ("TARGET_FILE_BASE_NAME static all properties" "$<TARGET_FILE_BASE_NAME:static3>" "static3_archive")
 check_value ("TARGET_LINKER_FILE_BASE_NAME static linker all properties" "$<TARGET_LINKER_FILE_BASE_NAME:static3>" "static3_archive")
 ]])
@@ -95,8 +95,8 @@ set_property (TARGET static4 PROPERTY ${FIRST_CONFIG}_POSTFIX _postfix)
 string (APPEND GENERATE_CONTENT [[
 
 check_value ("TARGET_FILE_BASE_NAME executable all properties + postfix" "$<TARGET_FILE_BASE_NAME:exec4>" "exec4_runtime_postfix")
-check_value ("TARGET_FILE_BASE_NAME shared all properties + postfix" "$<TARGET_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared4_runtime,shared4_library>_postfix")
-check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties + postfix" "$<TARGET_LINKER_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared4_archive,shared4_library>_postfix")
+check_value ("TARGET_FILE_BASE_NAME shared all properties + postfix" "$<TARGET_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared4_runtime,shared4_library>_postfix")
+check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties + postfix" "$<TARGET_LINKER_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared4_archive,shared4_library>_postfix")
 check_value ("TARGET_FILE_BASE_NAME static all properties + postfix" "$<TARGET_FILE_BASE_NAME:static4>" "static4_archive_postfix")
 check_value ("TARGET_LINKER_FILE_BASE_NAME static linker all properties + postfix" "$<TARGET_LINKER_FILE_BASE_NAME:static4>" "static4_archive_postfix")
 ]])
diff --git a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME.cmake b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME.cmake
index f88d710..1963244 100644
--- a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME.cmake
+++ b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_BASE_NAME.cmake
@@ -72,8 +72,8 @@ set_property (TARGET static3 PROPERTY PDB_NAME static3_pdb)
 string (APPEND GENERATE_CONTENT [[
 
 check_value ("TARGET_FILE_BASE_NAME executable all properties" "$<TARGET_FILE_BASE_NAME:exec3>" "exec3_runtime")
-check_value ("TARGET_FILE_BASE_NAME shared all properties" "$<TARGET_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared3_runtime,shared3_library>")
-check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties" "$<TARGET_LINKER_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared3_archive,shared3_library>")
+check_value ("TARGET_FILE_BASE_NAME shared all properties" "$<TARGET_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared3_runtime,shared3_library>")
+check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties" "$<TARGET_LINKER_FILE_BASE_NAME:shared3>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared3_archive,shared3_library>")
 check_value ("TARGET_FILE_BASE_NAME static all properties" "$<TARGET_FILE_BASE_NAME:static3>" "static3_archive")
 check_value ("TARGET_LINKER_FILE_BASE_NAME static linker all properties" "$<TARGET_LINKER_FILE_BASE_NAME:static3>" "static3_archive")
 ]])
@@ -118,8 +118,8 @@ set_property (TARGET static4 PROPERTY ${FIRST_CONFIG}_POSTFIX _postfix)
 string (APPEND GENERATE_CONTENT [[
 
 check_value ("TARGET_FILE_BASE_NAME executable all properties + postfix" "$<TARGET_FILE_BASE_NAME:exec4>" "exec4_runtime_postfix")
-check_value ("TARGET_FILE_BASE_NAME shared all properties + postfix" "$<TARGET_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared4_runtime,shared4_library>_postfix")
-check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties + postfix" "$<TARGET_LINKER_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN>,shared4_archive,shared4_library>_postfix")
+check_value ("TARGET_FILE_BASE_NAME shared all properties + postfix" "$<TARGET_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared4_runtime,shared4_library>_postfix")
+check_value ("TARGET_LINKER_FILE_BASE_NAME shared linker all properties + postfix" "$<TARGET_LINKER_FILE_BASE_NAME:shared4>" "$<IF:$<IN_LIST:$<PLATFORM_ID>,Windows$<SEMICOLON>CYGWIN$<SEMICOLON>MSYS>,shared4_archive,shared4_library>_postfix")
 check_value ("TARGET_FILE_BASE_NAME static all properties + postfix" "$<TARGET_FILE_BASE_NAME:static4>" "static4_archive_postfix")
 check_value ("TARGET_LINKER_FILE_BASE_NAME static linker all properties + postfix" "$<TARGET_LINKER_FILE_BASE_NAME:static4>" "static4_archive_postfix")
 ]])
diff --git a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX-imported-target.cmake b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX-imported-target.cmake
index f52776e..cc9cd5a 100644
--- a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX-imported-target.cmake
+++ b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX-imported-target.cmake
@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.14)
 
 enable_language (C)
 
-set (win_platforms Windows CYGWIN)
+set (win_platforms Windows CYGWIN MSYS)
 
 set (GENERATE_CONTENT [[
 macro (CHECK_VALUE test_msg value expected)
diff --git a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX.cmake b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX.cmake
index bef7bbf..edfb40c 100644
--- a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX.cmake
+++ b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_PREFIX.cmake
@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.14)
 
 enable_language (C)
 
-set (win_platforms Windows CYGWIN)
+set (win_platforms Windows CYGWIN MSYS)
 
 set (GENERATE_CONTENT [[
 macro (CHECK_VALUE test_msg value expected)
diff --git a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX-imported-target.cmake b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX-imported-target.cmake
index cefeb86..3ee42a5 100644
--- a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX-imported-target.cmake
+++ b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX-imported-target.cmake
@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.14)
 
 enable_language (C)
 
-set (win_platforms Windows CYGWIN)
+set (win_platforms Windows CYGWIN MSYS)
 
 set (GENERATE_CONTENT [[
 macro (CHECK_VALUE test_msg value expected)
diff --git a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX.cmake b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX.cmake
index 39e39fd..1fe75d9 100644
--- a/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX.cmake
+++ b/Tests/RunCMake/GenEx-TARGET_FILE/TARGET_FILE_SUFFIX.cmake
@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.14)
 
 enable_language (C)
 
-set (win_platforms Windows CYGWIN)
+set (win_platforms Windows CYGWIN MSYS)
 
 set (GENERATE_CONTENT [[
 macro (CHECK_VALUE test_msg value expected)
diff --git a/Tests/RunCMake/GenerateExportHeader/exportheader_test.cpp b/Tests/RunCMake/GenerateExportHeader/exportheader_test.cpp
index dcaa4f2..ed8c35e 100644
--- a/Tests/RunCMake/GenerateExportHeader/exportheader_test.cpp
+++ b/Tests/RunCMake/GenerateExportHeader/exportheader_test.cpp
@@ -8,6 +8,14 @@
 #include "libshared.h"
 #include "libstatic.h"
 
+static void rtrim(std::string& str, char byte)
+{
+  const std::size_t size = str.size();
+  if (size && str[size - 1] == byte) {
+    str.resize(size - 1);
+  }
+}
+
 void compare(const char* refName, const char* testName)
 {
   std::ifstream ref;
@@ -31,16 +39,14 @@ void compare(const char* refName, const char* testName)
     // Some very old Borland runtimes (C++ Builder 5 WITHOUT Update 1) add a
     // trailing null to the string that we need to strip before testing for a
     // trailing space.
-    if (refLine.size() && refLine[refLine.size() - 1] == 0) {
-      refLine.resize(refLine.size() - 1);
-    }
-    if (testLine.size() && testLine[testLine.size() - 1] == 0) {
-      testLine.resize(testLine.size() - 1);
-    }
+    rtrim(refLine, 0);
+    rtrim(testLine, 0);
     // The reference files never have trailing spaces:
-    if (testLine.size() && testLine[testLine.size() - 1] == ' ') {
-      testLine.resize(testLine.size() - 1);
-    }
+    rtrim(testLine, ' ');
+    // Strip trailing CR. LF is not returned by getline, but CR is returned
+    // on some platforms.
+    rtrim(refLine, '\r');
+    rtrim(testLine, '\r');
     if (refLine != testLine) {
       std::cout << "Ref and test are not the same:\n  Ref:  \"" << refLine
                 << "\"\n  Test: \"" << testLine << "\"\n";
diff --git a/Tests/RunCMake/RunCMake.cmake b/Tests/RunCMake/RunCMake.cmake
index 7994fc2..b4a57b2 100644
--- a/Tests/RunCMake/RunCMake.cmake
+++ b/Tests/RunCMake/RunCMake.cmake
@@ -23,10 +23,13 @@ function(run_cmake test)
   endif()
 
   string(TOLOWER ${CMAKE_HOST_SYSTEM_NAME} platform_name)
+  #remove all additional bits from cygwin/msys name
   if(platform_name MATCHES cygwin)
-    #remove all additional bits from cygwin name
     set(platform_name cygwin)
   endif()
+  if(platform_name MATCHES msys)
+    set(platform_name msys)
+  endif()
 
   foreach(o out err)
     if(RunCMake-std${o}-file AND EXISTS ${top_src}/${RunCMake-std${o}-file})
diff --git a/Tests/RunCMake/configure_file/NoSourcePermissions.cmake b/Tests/RunCMake/configure_file/NoSourcePermissions.cmake
index c6ad131..85533c4 100644
--- a/Tests/RunCMake/configure_file/NoSourcePermissions.cmake
+++ b/Tests/RunCMake/configure_file/NoSourcePermissions.cmake
@@ -1,7 +1,7 @@
 configure_file(NoSourcePermissions.sh NoSourcePermissions.sh.out
                NO_SOURCE_PERMISSIONS)
 
-if (UNIX)
+if (UNIX AND NOT MSYS)
   execute_process(COMMAND ${CMAKE_CURRENT_BINARY_DIR}/NoSourcePermissions.sh.out
                   RESULT_VARIABLE result)
   if (result EQUAL "0")
diff --git a/Tests/RunCMake/configure_file/SourcePermissions.cmake b/Tests/RunCMake/configure_file/SourcePermissions.cmake
index c4d3d61..f8c506a 100644
--- a/Tests/RunCMake/configure_file/SourcePermissions.cmake
+++ b/Tests/RunCMake/configure_file/SourcePermissions.cmake
@@ -6,7 +6,7 @@ configure_file(${CMAKE_CURRENT_SOURCE_DIR}/sourcefile.txt
         WORLD_READ
 )
 
-if (CMAKE_HOST_UNIX)
+if (CMAKE_HOST_UNIX AND NOT MSYS)
   find_program(STAT_EXECUTABLE NAMES stat)
   if(NOT STAT_EXECUTABLE)
     return()
diff --git a/Tests/RunCMake/file-CHMOD/RunCMakeTest.cmake b/Tests/RunCMake/file-CHMOD/RunCMakeTest.cmake
index c7bff15..18deb89 100644
--- a/Tests/RunCMake/file-CHMOD/RunCMakeTest.cmake
+++ b/Tests/RunCMake/file-CHMOD/RunCMakeTest.cmake
@@ -14,6 +14,6 @@ if(UNIX)
     OUTPUT_STRIP_TRAILING_WHITESPACE)
 endif()
 
-if(NOT WIN32 AND NOT "${uid}" STREQUAL "0")
+if(NOT WIN32 AND NOT MSYS AND NOT "${uid}" STREQUAL "0")
   run_cmake(CHMOD-write-only)
 endif()
diff --git a/Tests/RunCMake/file/RunCMakeTest.cmake b/Tests/RunCMake/file/RunCMakeTest.cmake
index 6d1109a..9efd3f4 100644
--- a/Tests/RunCMake/file/RunCMakeTest.cmake
+++ b/Tests/RunCMake/file/RunCMakeTest.cmake
@@ -87,7 +87,9 @@ run_cmake(GLOB-noexp-RELATIVE)
 run_cmake_command(GLOB-error-CONFIGURE_DEPENDS-SCRIPT_MODE ${CMAKE_COMMAND} -P
   ${RunCMake_SOURCE_DIR}/GLOB-error-CONFIGURE_DEPENDS-SCRIPT_MODE.cmake)
 
-if(NOT WIN32 OR CYGWIN)
+if(NOT WIN32
+    AND NOT MSYS # FIXME: This works on CYGWIN but not on MSYS
+    )
   run_cmake(CREATE_LINK-SYMBOLIC)
   run_cmake(CREATE_LINK-SYMBOLIC-noexist)
   run_cmake(GLOB_RECURSE-cyclic-recursion)
@@ -162,7 +164,9 @@ else()
   run_cmake_command(GLOB-CONFIGURE_DEPENDS-RerunCMake-rebuild_second ${CMAKE_COMMAND} --build .)
   run_cmake_command(GLOB-CONFIGURE_DEPENDS-RerunCMake-nowork ${CMAKE_COMMAND} --build .)
 
-  if(NOT WIN32 OR CYGWIN)
+  if(NOT WIN32
+      AND NOT MSYS # FIXME: This works on CYGWIN but not on MSYS
+      )
     message(STATUS "GLOB-CONFIGURE_DEPENDS-CMP0009-RerunCMake: link the first test directory into a new directory...")
     file(MAKE_DIRECTORY "${RunCMake_TEST_BINARY_DIR}/test2")
     execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${RunCMake_TEST_BINARY_DIR}/test" "${RunCMake_TEST_BINARY_DIR}/test2/test_folder_symlink")
diff --git a/Tests/RunCMake/find_file/FromPATHEnv-stdout-msys.txt b/Tests/RunCMake/find_file/FromPATHEnv-stdout-msys.txt
new file mode 100644
index 0000000..6912bdf
--- /dev/null
+++ b/Tests/RunCMake/find_file/FromPATHEnv-stdout-msys.txt
@@ -0,0 +1,9 @@
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
+-- PrefixInPATH_File='.*/Tests/RunCMake/find_file/include/PrefixInPATH.h'
+-- PrefixInPATH_File='.*/Tests/RunCMake/find_file/include/PrefixInPATH.h'
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
+-- PrefixInPATH_File='PrefixInPATH_File-NOTFOUND'
diff --git a/Tests/RunCMake/find_file/PrefixInPATH-stdout-msys.txt b/Tests/RunCMake/find_file/PrefixInPATH-stdout-msys.txt
new file mode 100644
index 0000000..d73bc1d
--- /dev/null
+++ b/Tests/RunCMake/find_file/PrefixInPATH-stdout-msys.txt
@@ -0,0 +1,4 @@
+-- PrefixInPATH_INCLUDE_DIR='PrefixInPATH_INCLUDE_DIR-NOTFOUND'
+-- PrefixInPATH_INCLUDE_DIR='.*/Tests/RunCMake/find_file/include/PrefixInPATH.h'
+-- PrefixInPATH_INCLUDE_DIR='.*/Tests/RunCMake/find_file/include/PrefixInPATH.h'
+-- PrefixInPATH_INCLUDE_DIR='.*/Tests/RunCMake/find_file/include/PrefixInPATH.h'
diff --git a/Tests/RunCMake/find_library/FromPATHEnv-stdout-msys.txt b/Tests/RunCMake/find_library/FromPATHEnv-stdout-msys.txt
new file mode 100644
index 0000000..01e2720
--- /dev/null
+++ b/Tests/RunCMake/find_library/FromPATHEnv-stdout-msys.txt
@@ -0,0 +1,6 @@
+-- CREATED_LIBRARY='CREATED_LIBRARY-NOTFOUND'
+-- CREATED_LIBRARY='[^']*/Tests/RunCMake/find_library/FromPATHEnv-build/lib/libcreated.a'
+-- CREATED_LIBRARY='[^']*/Tests/RunCMake/find_library/FromPATHEnv-build/lib/libcreated.a'
+-- CREATED_LIBRARY='CREATED_LIBRARY-NOTFOUND'
+-- CREATED_LIBRARY='CREATED_LIBRARY-NOTFOUND'
+-- CREATED_LIBRARY='CREATED_LIBRARY-NOTFOUND'
diff --git a/Tests/RunCMake/find_library/PrefixInPATH-stdout-msys.txt b/Tests/RunCMake/find_library/PrefixInPATH-stdout-msys.txt
new file mode 100644
index 0000000..1ab884c
--- /dev/null
+++ b/Tests/RunCMake/find_library/PrefixInPATH-stdout-msys.txt
@@ -0,0 +1,4 @@
+-- PrefixInPATH_LIBRARY='PrefixInPATH_LIBRARY-NOTFOUND'
+-- PrefixInPATH_LIBRARY='.*/Tests/RunCMake/find_library/lib/libPrefixInPATH.a'
+-- PrefixInPATH_LIBRARY='.*/Tests/RunCMake/find_library/lib/libPrefixInPATH.a'
+-- PrefixInPATH_LIBRARY='.*/Tests/RunCMake/find_library/lib/libPrefixInPATH.a'
diff --git a/Tests/RunCMake/find_package/RunCMakeTest.cmake b/Tests/RunCMake/find_package/RunCMakeTest.cmake
index a899f46..72ffcce 100644
--- a/Tests/RunCMake/find_package/RunCMakeTest.cmake
+++ b/Tests/RunCMake/find_package/RunCMakeTest.cmake
@@ -40,6 +40,8 @@ run_cmake(VersionRangeConfig)
 run_cmake(VersionRangeConfig2)
 run_cmake(VersionRangeConfigStd)
 run_cmake(VersionRangeConfigStd2)
-if(UNIX)
+if(UNIX
+    AND NOT MSYS # FIXME: This works on CYGWIN but not on MSYS
+    )
   run_cmake(SetFoundResolved)
 endif()
diff --git a/Tests/RunCMake/find_path/FromPATHEnv-stdout-msys.txt b/Tests/RunCMake/find_path/FromPATHEnv-stdout-msys.txt
new file mode 100644
index 0000000..8f3e7ca
--- /dev/null
+++ b/Tests/RunCMake/find_path/FromPATHEnv-stdout-msys.txt
@@ -0,0 +1,9 @@
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
+-- PATH_IN_ENV_PATH='.*/Tests/RunCMake/find_path/include'
+-- PATH_IN_ENV_PATH='.*/Tests/RunCMake/find_path/include'
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
+-- PATH_IN_ENV_PATH='PATH_IN_ENV_PATH-NOTFOUND'
diff --git a/Tests/RunCMake/find_path/PrefixInPATH-stdout-msys.txt b/Tests/RunCMake/find_path/PrefixInPATH-stdout-msys.txt
new file mode 100644
index 0000000..bb2ceb7
--- /dev/null
+++ b/Tests/RunCMake/find_path/PrefixInPATH-stdout-msys.txt
@@ -0,0 +1,4 @@
+-- PrefixInPATH_INCLUDE_DIR='PrefixInPATH_INCLUDE_DIR-NOTFOUND'
+-- PrefixInPATH_INCLUDE_DIR='.*/Tests/RunCMake/find_path/include'
+-- PrefixInPATH_INCLUDE_DIR='.*/Tests/RunCMake/find_path/include'
+-- PrefixInPATH_INCLUDE_DIR='.*/Tests/RunCMake/find_path/include'
diff --git a/Tests/RunCMake/find_program/RunCMakeTest.cmake b/Tests/RunCMake/find_program/RunCMakeTest.cmake
index 3e23920..77c021d 100644
--- a/Tests/RunCMake/find_program/RunCMakeTest.cmake
+++ b/Tests/RunCMake/find_program/RunCMakeTest.cmake
@@ -6,7 +6,7 @@ run_cmake(NamesPerDir)
 run_cmake(RelAndAbsPath)
 run_cmake(Required)
 
-if(CMAKE_SYSTEM_NAME MATCHES "^(Windows|CYGWIN)$")
+if(CMAKE_SYSTEM_NAME MATCHES "^(Windows|CYGWIN|MSYS)$")
   run_cmake(WindowsCom)
   run_cmake(WindowsExe)
 else()
diff --git a/Tests/RunCMake/install/TARGETS-Defaults-Cache-all-check.cmake b/Tests/RunCMake/install/TARGETS-Defaults-Cache-all-check.cmake
index 4a55cd6..d099469 100644
--- a/Tests/RunCMake/install/TARGETS-Defaults-Cache-all-check.cmake
+++ b/Tests/RunCMake/install/TARGETS-Defaults-Cache-all-check.cmake
@@ -13,6 +13,21 @@ if(WIN32)
     [[mylib/(lib)?lib1\.(dll\.a|lib)]]
     [[mylib/(lib)?lib2\.(a|lib)]]
     )
+elseif(MSYS)
+  set(_check_files
+    [[lib3]]
+    [[lib3/liblib3\.dll\.a]]
+    [[lib4]]
+    [[lib4/msys-lib4\.dll]]
+    [[mybin]]
+    [[mybin/exe\.exe]]
+    [[mybin/msys-lib1\.dll]]
+    [[myinclude]]
+    [[myinclude/obj3\.h]]
+    [[mylib]]
+    [[mylib/liblib1\.dll\.a]]
+    [[mylib/liblib2\.a]]
+    )
 elseif(CYGWIN)
   set(_check_files
     [[lib3]]
diff --git a/Tests/RunCMake/install/TARGETS-Defaults-all-check.cmake b/Tests/RunCMake/install/TARGETS-Defaults-all-check.cmake
index 30f2266..6e13b84 100644
--- a/Tests/RunCMake/install/TARGETS-Defaults-all-check.cmake
+++ b/Tests/RunCMake/install/TARGETS-Defaults-all-check.cmake
@@ -15,6 +15,23 @@ if(WIN32)
     [[lib4]]
     [[lib4/(lib)?lib4\.dll]]
     )
+elseif(MSYS)
+  set(_check_files
+    [[bin]]
+    [[bin/exe\.exe]]
+    [[bin/msys-lib1\.dll]]
+    [[include]]
+    [[include/obj1\.h]]
+    [[include/obj2\.h]]
+    [[include/obj3\.h]]
+    [[lib]]
+    [[lib/liblib1\.dll\.a]]
+    [[lib/liblib2\.a]]
+    [[lib3]]
+    [[lib3/liblib3\.dll\.a]]
+    [[lib4]]
+    [[lib4/msys-lib4\.dll]]
+    )
 elseif(CYGWIN)
   set(_check_files
     [[bin]]
diff --git a/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-all-check.cmake b/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-all-check.cmake
index bc9ebd1..e602af9 100644
--- a/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-all-check.cmake
+++ b/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-all-check.cmake
@@ -8,6 +8,16 @@ if(WIN32)
     [[lib/(lib)?namelink-uns-dev\.dll]]
     [[lib/(lib)?namelink-uns\.dll]]
   )
+elseif(MSYS)
+  set(_check_files
+    [[lib]]
+    [[lib/msys-namelink-none\.dll]]
+    [[lib/msys-namelink-same-1\.dll]]
+    [[lib/msys-namelink-sep-1\.dll]]
+    [[lib/msys-namelink-skip-1\.dll]]
+    [[lib/msys-namelink-uns-1\.dll]]
+    [[lib/msys-namelink-uns-dev-1\.dll]]
+  )
 elseif(CYGWIN)
   set(_check_files
     [[lib]]
diff --git a/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-lib-check.cmake b/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-lib-check.cmake
index 3f6be68..cd579eb 100644
--- a/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-lib-check.cmake
+++ b/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-lib-check.cmake
@@ -6,6 +6,14 @@ if(WIN32)
     [[lib/(lib)?namelink-sep\.dll]]
     [[lib/(lib)?namelink-skip\.dll]]
   )
+elseif(MSYS)
+  set(_check_files
+    [[lib]]
+    [[lib/msys-namelink-none\.dll]]
+    [[lib/msys-namelink-same-1\.dll]]
+    [[lib/msys-namelink-sep-1\.dll]]
+    [[lib/msys-namelink-skip-1\.dll]]
+  )
 elseif(CYGWIN)
   set(_check_files
     [[lib]]
diff --git a/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-uns-check.cmake b/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-uns-check.cmake
index 0033c88..ea68f4a 100644
--- a/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-uns-check.cmake
+++ b/Tests/RunCMake/install/TARGETS-NAMELINK_COMPONENT-uns-check.cmake
@@ -4,6 +4,12 @@ if(WIN32)
     [[lib/(lib)?namelink-uns-dev\.dll]]
     [[lib/(lib)?namelink-uns\.dll]]
   )
+elseif(MSYS)
+  set(_check_files
+    [[lib]]
+    [[lib/msys-namelink-uns-1\.dll]]
+    [[lib/msys-namelink-uns-dev-1\.dll]]
+  )
 elseif(CYGWIN)
   set(_check_files
     [[lib]]
diff --git a/Tests/RunCMake/install/TARGETS-OUTPUT_NAME-all-check.cmake b/Tests/RunCMake/install/TARGETS-OUTPUT_NAME-all-check.cmake
index 5daecc8..91d5ef0 100644
--- a/Tests/RunCMake/install/TARGETS-OUTPUT_NAME-all-check.cmake
+++ b/Tests/RunCMake/install/TARGETS-OUTPUT_NAME-all-check.cmake
@@ -4,6 +4,8 @@ if(WIN32)
   set(test45 [[bin/test4\.dll;bin/test4\.lib;bin/test5ar\.lib]])
 
   check_installed("^bin;(${libtest45};${test123})|(${test123};${test45})\$")
+elseif(MSYS)
+  check_installed([[^bin;bin/libtest4\.dll\.a;bin/libtest5ar\.a;bin/msys-test4\.dll;bin/test1out\.exe;bin/test2deb\.exe;bin/test3exc\.exe$]])
 elseif(CYGWIN)
   check_installed([[^bin;bin/cygtest4\.dll;bin/libtest4\.dll\.a;bin/libtest5ar\.a;bin/test1out\.exe;bin/test2deb\.exe;bin/test3exc\.exe$]])
 elseif(APPLE)
diff --git a/Tests/SetLang/CMakeLists.txt b/Tests/SetLang/CMakeLists.txt
index 3eb9185..80348ab 100644
--- a/Tests/SetLang/CMakeLists.txt
+++ b/Tests/SetLang/CMakeLists.txt
@@ -9,6 +9,10 @@ set_source_files_properties(foo.c bar.c PROPERTIES LANGUAGE CXX)
 target_link_libraries(SetLang foo)
 set_target_properties(SetLang PROPERTIES LINKER_LANGUAGE CXX)
 
+# Windows defender blocks SetLang executable (https://cygwin.com/pipermail/cygwin/2021-January/247508.html)
+# Coordinate this name with 'Tests/CMakeLists.txt'.
+set_target_properties(SetLang PROPERTIES OUTPUT_NAME "SetLangX")
+
 # VS generators historically tolerated target-wide -TP flags added
 # by project code, so cover that case to preserve the behavior.
 if(CMAKE_GENERATOR MATCHES "^Visual Studio" AND "x${CMAKE_C_COMPILER_ID}" STREQUAL "xMSVC")
diff --git a/Utilities/cmlibuv/CMakeLists.txt b/Utilities/cmlibuv/CMakeLists.txt
index a4f0148..086345c 100644
--- a/Utilities/cmlibuv/CMakeLists.txt
+++ b/Utilities/cmlibuv/CMakeLists.txt
@@ -156,7 +156,7 @@ if(CMAKE_SYSTEM_NAME STREQUAL "OS400")
     )
 endif()
 
-if(CMAKE_SYSTEM_NAME MATCHES "CYGWIN")
+if(CMAKE_SYSTEM_NAME MATCHES "CYGWIN" OR CMAKE_SYSTEM_NAME MATCHES "MSYS")
   list(APPEND uv_libraries
     )
   list(APPEND uv_headers
diff --git a/bootstrap b/bootstrap
index 2a81ef2..aefd210 100755
--- a/bootstrap
+++ b/bootstrap
@@ -97,8 +97,17 @@ else
   cmake_system_cygwin=false
 fi
 
+# Determine whether this is a MSYS environment.
+if echo "${cmake_system}" | grep MSYS >/dev/null 2>&1; then
+  cmake_system_msys=true
+  cmake_doc_dir_keyword="MSYS"
+  cmake_man_dir_keyword="MSYS"
+else
+  cmake_system_msys=false
+fi
+
 # Determine whether this is a MinGW environment.
-if echo "${cmake_system}" | grep 'MINGW\|MSYS' >/dev/null 2>&1; then
+if echo "${cmake_system}" | grep 'MINGW' >/dev/null 2>&1; then
   cmake_system_mingw=true
 else
   cmake_system_mingw=false
@@ -1071,7 +1080,7 @@ else
 fi
 
 # Add Cygwin-specific flags
-if ${cmake_system_cygwin}; then
+if ${cmake_system_cygwin} || ${cmake_system_msys}; then
   cmake_ld_flags="${LDFLAGS} -Wl,--enable-auto-import"
 fi
 
@@ -1096,6 +1105,7 @@ cmake_toolchains=''
 case "${cmake_system}" in
   *AIX*)   cmake_toolchains='XL GNU' ;;
   *CYGWIN*) cmake_toolchains='GNU' ;;
+  *MSYS*) cmake_toolchains='GNU' ;;
   *Darwin*) cmake_toolchains='Clang GNU' ;;
   *Linux*) cmake_toolchains='GNU Clang XL PGI PathScale' ;;
   *MINGW*) cmake_toolchains='GNU' ;;