Do not initialize NO_SYSTEM_FROM_IMPORTED on INTERFACE libraries

The change in commit v3.8.0-rc1~276^2 (Allow NO_SYSTEM_FROM_IMPORTED on
imported INTERFACE libraries, 2016-11-21) was incorrect.  The property
is not meant to be set on imported targets at all.  It is meant to be
set on their consumers that compile sources.  Since INTERFACE libraries
have no sources to compile, the property is not needed on them.

Revert most of that change.  Unfortunately we must still tolerate
project code setting NO_SYSTEM_FROM_IMPORTED on INTERFACE libraries
because they were allowed by CMake 3.8 and 3.9.

Issue: #17348

4 files changed, 9 insertions, 7 deletions

diff --git a/Help/manual/cmake-buildsystem.7.rst b/Help/manual/cmake-buildsystem.7.rst
index debaf23..5cfe725 100644
--- a/Help/manual/cmake-buildsystem.7.rst
+++ b/Help/manual/cmake-buildsystem.7.rst
@@ -970,7 +970,6 @@ are:
 * ``EXPORT_NAME``
 * ``IMPORTED``
 * ``NAME``
-* ``NO_SYSTEM_FROM_IMPORTED``
 * Properties matching ``IMPORTED_LIBNAME_*``
 * Properties matching ``MAP_IMPORTED_CONFIG_*``
 
diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
index 7a3cc76..c6cd502 100644
--- a/Source/cmTarget.cxx
+++ b/Source/cmTarget.cxx
@@ -256,6 +256,7 @@ cmTarget::cmTarget(std::string const& name, cmStateEnums::TargetType type,
     this->SetPropertyDefault("WIN32_EXECUTABLE", nullptr);
     this->SetPropertyDefault("MACOSX_BUNDLE", nullptr);
     this->SetPropertyDefault("MACOSX_RPATH", nullptr);
+    this->SetPropertyDefault("NO_SYSTEM_FROM_IMPORTED", nullptr);
     this->SetPropertyDefault("BUILD_WITH_INSTALL_NAME_DIR", nullptr);
     this->SetPropertyDefault("C_CLANG_TIDY", nullptr);
     this->SetPropertyDefault("C_COMPILER_LAUNCHER", nullptr);
@@ -282,10 +283,6 @@ cmTarget::cmTarget(std::string const& name, cmStateEnums::TargetType type,
     this->SetPropertyDefault("LINK_SEARCH_END_STATIC", nullptr);
   }
 
-  if (this->GetType() != cmStateEnums::UTILITY) {
-    this->SetPropertyDefault("NO_SYSTEM_FROM_IMPORTED", nullptr);
-  }
-
   // Collect the set of configuration types.
   std::vector<std::string> configNames;
   mf->GetConfigurations(configNames);
diff --git a/Source/cmTargetPropertyComputer.cxx b/Source/cmTargetPropertyComputer.cxx
index 3a3c165..1d2520d 100644
--- a/Source/cmTargetPropertyComputer.cxx
+++ b/Source/cmTargetPropertyComputer.cxx
@@ -66,12 +66,19 @@ bool cmTargetPropertyComputer::WhiteListedInterfaceProperty(
   }
 
   if (prop == "IMPORTED_CONFIGURATIONS" || prop == "IMPORTED_LIBNAME" ||
-      prop == "NO_SYSTEM_FROM_IMPORTED" ||
       cmHasLiteralPrefix(prop, "IMPORTED_LIBNAME_") ||
       cmHasLiteralPrefix(prop, "MAP_IMPORTED_CONFIG_")) {
     return true;
   }
 
+  // This property should not be allowed but was incorrectly added in
+  // CMake 3.8.  We can't remove it from the whitelist without breaking
+  // projects that try to set it.  One day we could warn about this, but
+  // for now silently accept it.
+  if (prop == "NO_SYSTEM_FROM_IMPORTED") {
+    return true;
+  }
+
   return false;
 }
 
diff --git a/Tests/InterfaceLibrary/CMakeLists.txt b/Tests/InterfaceLibrary/CMakeLists.txt
index 33c4b90..3db210a 100644
--- a/Tests/InterfaceLibrary/CMakeLists.txt
+++ b/Tests/InterfaceLibrary/CMakeLists.txt
@@ -64,7 +64,6 @@ target_link_libraries(iface_whitelist INTERFACE $<$<BOOL:$<TARGET_PROPERTY:CUSTO
 add_executable(exec_whitelist dummy.cpp)
 target_link_libraries(exec_whitelist iface_whitelist)
 
-set(CMAKE_NO_SYSTEM_FROM_IMPORTED 1)
 add_library(iface_imported INTERFACE IMPORTED)
 set_property(TARGET iface_imported PROPERTY
   INTERFACE_COMPILE_DEFINITIONS