Link step: use linker dependency linker file

Based on work done by @ben.boeckel (!8051)

Fixes: #22217

12 files changed, 124 insertions, 27 deletions

diff --git a/Tests/CMakeLib/testGccDepfileReader_data/deps1.txt b/Tests/CMakeLib/testGccDepfileReader_data/deps1.txt
index fd2679f..4207b58 100644
--- a/Tests/CMakeLib/testGccDepfileReader_data/deps1.txt
+++ b/Tests/CMakeLib/testGccDepfileReader_data/deps1.txt
@@ -1,26 +1,26 @@
 --RULES--
 main.o
 --DEPENDENCIES--
-main.cpp
+/usr/include/features.h
 /usr/include/stdc-predef.h
 /usr/include/stdio.h
 /usr/include/x86_64-linux-gnu/bits/libc-header-start.h
-/usr/include/features.h
-/usr/include/x86_64-linux-gnu/sys/cdefs.h
-/usr/include/x86_64-linux-gnu/bits/wordsize.h
 /usr/include/x86_64-linux-gnu/bits/long-double.h
-/usr/include/x86_64-linux-gnu/gnu/stubs.h
-/usr/include/x86_64-linux-gnu/gnu/stubs-64.h
-/usr/lib/gcc/x86_64-linux-gnu/8/include/stddef.h
-/usr/lib/gcc/x86_64-linux-gnu/8/include/stdarg.h
+/usr/include/x86_64-linux-gnu/bits/stdio_lim.h
+/usr/include/x86_64-linux-gnu/bits/sys_errlist.h
 /usr/include/x86_64-linux-gnu/bits/types.h
-/usr/include/x86_64-linux-gnu/bits/typesizes.h
+/usr/include/x86_64-linux-gnu/bits/types/FILE.h
+/usr/include/x86_64-linux-gnu/bits/types/__FILE.h
+/usr/include/x86_64-linux-gnu/bits/types/__fpos64_t.h
 /usr/include/x86_64-linux-gnu/bits/types/__fpos_t.h
 /usr/include/x86_64-linux-gnu/bits/types/__mbstate_t.h
-/usr/include/x86_64-linux-gnu/bits/types/__fpos64_t.h
-/usr/include/x86_64-linux-gnu/bits/types/__FILE.h
-/usr/include/x86_64-linux-gnu/bits/types/FILE.h
-/usr/include/x86_64-linux-gnu/bits/types/struct_FILE.h
 /usr/include/x86_64-linux-gnu/bits/types/cookie_io_functions_t.h
-/usr/include/x86_64-linux-gnu/bits/stdio_lim.h
-/usr/include/x86_64-linux-gnu/bits/sys_errlist.h
+/usr/include/x86_64-linux-gnu/bits/types/struct_FILE.h
+/usr/include/x86_64-linux-gnu/bits/typesizes.h
+/usr/include/x86_64-linux-gnu/bits/wordsize.h
+/usr/include/x86_64-linux-gnu/gnu/stubs-64.h
+/usr/include/x86_64-linux-gnu/gnu/stubs.h
+/usr/include/x86_64-linux-gnu/sys/cdefs.h
+/usr/lib/gcc/x86_64-linux-gnu/8/include/stdarg.h
+/usr/lib/gcc/x86_64-linux-gnu/8/include/stddef.h
+main.cpp
diff --git a/Tests/CMakeLib/testGccDepfileReader_data/deps3.txt b/Tests/CMakeLib/testGccDepfileReader_data/deps3.txt
index 448f69c..8d82c60 100644
--- a/Tests/CMakeLib/testGccDepfileReader_data/deps3.txt
+++ b/Tests/CMakeLib/testGccDepfileReader_data/deps3.txt
@@ -1,11 +1,11 @@
 --RULES--
 main.o
 --DEPENDENCIES--
-main.cpp
-foo#bar.h
-foo\#bar.h
 foo bar.h
+foo#bar.h
+foo$bar.h
 foo\ bar.h
+foo\#bar.h
 foo\\ bar.h
 foo\\\\
-foo$bar.h
+main.cpp
diff --git a/Tests/RunCMake/BuildDepends/LinkDepends.cmake b/Tests/RunCMake/BuildDepends/LinkDepends.cmake
new file mode 100644
index 0000000..a414e03
--- /dev/null
+++ b/Tests/RunCMake/BuildDepends/LinkDepends.cmake
@@ -0,0 +1,22 @@
+
+enable_language(C)
+
+include("${CMAKE_BINARY_DIR}/../LinkDependsExternalLibrary-build/ExternalLibrary-debug.cmake")
+cmake_path(GET EXTERNAL_LIBRARY PARENT_PATH EXTERNAL_DIR)
+
+add_library(LinkDependsLib SHARED "${CMAKE_CURRENT_BINARY_DIR}/lib_depends.c")
+target_link_directories(LinkDependsLib PRIVATE "${EXTERNAL_DIR}")
+target_link_libraries(LinkDependsLib PRIVATE External)
+
+add_executable(LinkDependsExe "${CMAKE_CURRENT_BINARY_DIR}/exe_depends.c")
+target_link_directories(LinkDependsExe PRIVATE "${EXTERNAL_DIR}")
+target_link_libraries(LinkDependsExe PRIVATE External)
+
+
+file(GENERATE  OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/check-$<LOWER_CASE:$<CONFIG>>.cmake"
+  CONTENT "
+set(check_pairs
+  \"$<TARGET_FILE:LinkDependsLib>|${EXTERNAL_LIBRARY}\"
+  \"$<TARGET_FILE:LinkDependsExe>|${EXTERNAL_LIBRARY}\"
+  )
+")
diff --git a/Tests/RunCMake/BuildDepends/LinkDepends.step1.cmake b/Tests/RunCMake/BuildDepends/LinkDepends.step1.cmake
new file mode 100644
index 0000000..5ce55b0
--- /dev/null
+++ b/Tests/RunCMake/BuildDepends/LinkDepends.step1.cmake
@@ -0,0 +1,23 @@
+
+file(WRITE "${RunCMake_TEST_BINARY_DIR}/lib_depends.c" [[
+
+extern void external(void);
+
+void lib_depends(void)
+{
+  external();
+}
+]])
+
+
+file(WRITE "${RunCMake_TEST_BINARY_DIR}/exe_depends.c" [[
+
+extern void external(void);
+
+int main(void)
+{
+  external();
+
+  return 0;
+}
+]])
diff --git a/Tests/RunCMake/BuildDepends/LinkDepends.step2.cmake b/Tests/RunCMake/BuildDepends/LinkDepends.step2.cmake
new file mode 100644
index 0000000..f2c0067
--- /dev/null
+++ b/Tests/RunCMake/BuildDepends/LinkDepends.step2.cmake
@@ -0,0 +1,4 @@
+
+include ("${RunCMake_TEST_BINARY_DIR}/../LinkDependsExternalLibrary-build/ExternalLibrary-debug.cmake")
+
+file(TOUCH "${EXTERNAL_LIBRARY}")
diff --git a/Tests/RunCMake/BuildDepends/LinkDependsCheck.cmake b/Tests/RunCMake/BuildDepends/LinkDependsCheck.cmake
new file mode 100644
index 0000000..a21096b
--- /dev/null
+++ b/Tests/RunCMake/BuildDepends/LinkDependsCheck.cmake
@@ -0,0 +1,11 @@
+
+enable_language(C)
+
+file(WRITE "${CMAKE_BINARY_DIR}/LinkDependsUseLinker.cmake"
+     "set(CMAKE_C_LINK_DEPENDS_USE_LINKER \"${CMAKE_C_LINK_DEPENDS_USE_LINKER}\")\n")
+
+
+file(GENERATE  OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/check-$<LOWER_CASE:$<CONFIG>>.cmake"
+  CONTENT "
+# no required actions
+")
diff --git a/Tests/RunCMake/BuildDepends/LinkDependsExternalLibrary.cmake b/Tests/RunCMake/BuildDepends/LinkDependsExternalLibrary.cmake
new file mode 100644
index 0000000..fe6575c
--- /dev/null
+++ b/Tests/RunCMake/BuildDepends/LinkDependsExternalLibrary.cmake
@@ -0,0 +1,13 @@
+
+enable_language(C)
+
+add_library(External SHARED "${CMAKE_CURRENT_BINARY_DIR}/external.c")
+
+file(GENERATE OUTPUT "${CMAKE_BINARY_DIR}/ExternalLibrary-$<LOWER_CASE:$<CONFIG>>.cmake"
+  CONTENT "set(EXTERNAL_LIBRARY \"$<TARGET_LINKER_FILE:External>\")\n")
+
+
+file(GENERATE  OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/check-$<LOWER_CASE:$<CONFIG>>.cmake"
+  CONTENT "
+# no required actions
+")
diff --git a/Tests/RunCMake/BuildDepends/LinkDependsExternalLibrary.step1.cmake b/Tests/RunCMake/BuildDepends/LinkDependsExternalLibrary.step1.cmake
new file mode 100644
index 0000000..df302f7
--- /dev/null
+++ b/Tests/RunCMake/BuildDepends/LinkDependsExternalLibrary.step1.cmake
@@ -0,0 +1,11 @@
+
+file(WRITE "${RunCMake_TEST_BINARY_DIR}/external.c" [[
+
+
+#if defined(_WIN32)
+__declspec(dllexport)
+#endif
+  void external(void)
+{
+}
+]])
diff --git a/Tests/RunCMake/BuildDepends/RunCMakeTest.cmake b/Tests/RunCMake/BuildDepends/RunCMakeTest.cmake
index 8099079..b527580 100644
--- a/Tests/RunCMake/BuildDepends/RunCMakeTest.cmake
+++ b/Tests/RunCMake/BuildDepends/RunCMakeTest.cmake
@@ -194,3 +194,15 @@ if(RunCMake_GENERATOR MATCHES "^Visual Studio 9 " OR
 endif()
 run_BuildDepends(CustomCommandUnityBuild)
 unset(run_BuildDepends_skip_step_2)
+
+#if (RunCMake_GENERATOR MATCHES "Make|Ninja" AND CMAKE_C_LINK_DEPENDS_USE_LINKER)
+if (RunCMake_GENERATOR MATCHES "Make|Ninja")
+  set(run_BuildDepends_skip_step_2 1)
+  run_BuildDepends(LinkDependsCheck)
+  include("${RunCMake_BINARY_DIR}/LinkDependsCheck-build/LinkDependsUseLinker.cmake")
+  if (CMAKE_C_LINK_DEPENDS_USE_LINKER)
+    run_BuildDepends(LinkDependsExternalLibrary)
+    unset(run_BuildDepends_skip_step_2)
+    run_BuildDepends(LinkDepends)
+  endif()
+endif()
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 32ccef0..ada9132 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -295,6 +295,7 @@ endif()
 add_RunCMake_test(BuildDepends
   -DMSVC_VERSION=${MSVC_VERSION}
   -DCMAKE_C_COMPILER_ID=${CMAKE_C_COMPILER_ID}
+  -DCMAKE_C_LINK_DEPENDS_USE_COMPILER=${CMAKE_C_LINK_DEPENDS_USE_COMPILER}
   -DCMake_TEST_BuildDepends_GNU_AS=${CMake_TEST_BuildDepends_GNU_AS}
   )
 if(UNIX AND "${CMAKE_GENERATOR}" MATCHES "Unix Makefiles|Ninja")
diff --git a/Tests/RunCMake/TransformDepfile/deps-unix.d.txt b/Tests/RunCMake/TransformDepfile/deps-unix.d.txt
index fbdecc0..2588181 100644
--- a/Tests/RunCMake/TransformDepfile/deps-unix.d.txt
+++ b/Tests/RunCMake/TransformDepfile/deps-unix.d.txt
@@ -1,8 +1,8 @@
 subdir/out1 \
   /home/build/out2: \
-  subdir/in1 \
-  /home/build/in2
+  /home/build/in2 \
+  subdir/in1
 subdir/out3 \
   /home/build/out4: \
-  subdir/in3 \
-  /home/build/in4
+  /home/build/in4 \
+  subdir/in3
diff --git a/Tests/RunCMake/TransformDepfile/deps-windows.d.txt b/Tests/RunCMake/TransformDepfile/deps-windows.d.txt
index e09ae37..805a4c8 100644
--- a/Tests/RunCMake/TransformDepfile/deps-windows.d.txt
+++ b/Tests/RunCMake/TransformDepfile/deps-windows.d.txt
@@ -1,8 +1,8 @@
 subdir/out1 \
   C:/build/out2: \
-  subdir/in1 \
-  C:/build/in2
+  C:/build/in2 \
+  subdir/in1
 subdir/out3 \
   C:/build/out4: \
-  subdir/in3 \
-  C:/build/in4
+  C:/build/in4 \
+  subdir/in3