prevent use of ProjectOptions_SRC_DIR as cache var

[ClausKlein]

if to project A and B use different version of project_options and
project C use A and B with CMP.cmake (FetchContents), there is a common CMakeCache variable used!

[ClausKlein]

I have problems to build the test on my native OSX with newest apple clang:

-- Build files have been written to: /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install
+ cmake --build ./cmake-build-test-x86_64-Debug/install
[4/9] Building CXX object CMakeFiles/main.dir/cmake_pch.hxx.pch
Checking /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/main.dir/cmake_pch.hxx.cxx ...
Checking /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/main.dir/cmake_pch.hxx.cxx: FMT_LOCALE=1...
[5/9] Building CXX object CMakeFiles/lib2.dir/cmake_pch.hxx.pch
Checking /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/lib2.dir/cmake_pch.hxx.cxx ...
Checking /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/lib2.dir/cmake_pch.hxx.cxx: FMT_LOCALE=1...
[6/9] Building CXX object CMakeFiles/main.dir/src/main/main.cpp.o
FAILED: CMakeFiles/main.dir/src/main/main.cpp.o 
/usr/local/Cellar/cmake/3.24.1/bin/cmake -E __run_co_compile --launcher=/usr/local/bin/ccache --tidy="/usr/local/opt/llvm/bin/clang-tidy;-extra-arg=-Wno-unknown-warning-option;-extra-arg=-std=c++20;--extra-arg-before=--driver-mode=g++" --cppcheck="/usr/local/bin/cppcheck;--template=gcc;--enable=style,performance,warning,portability;--inline-suppr;--suppress=internalAstError;--suppress=unmatchedSuppression;--inconclusive;--std=c++20" --source=/Users/clausklein/cmake/project_options/test/src/main/main.cpp -- /Applications/Xcode.app/Contents/Developer/usr/bin/g++ -DFMT_LOCALE -isystem /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/vcpkg_installed/x64-osx/include -isystem /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/vcpkg_installed/x64-osx/include/eigen3 -g -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk -fcolor-diagnostics -march=native --coverage -O0 -g -fsanitize=address,undefined -Wall -Wextra -Wextra-semi -Wshadow -Wnon-virtual-dtor -Wold-style-cast -Wcast-align -Wunused -Woverloaded-virtual -Wpedantic -Wconversion -Wsign-conversion -Wnull-dereference -Wdouble-promotion -Wformat=2 -Wimplicit-fallthrough -std=c++20 -Winvalid-pch -Xclang -include-pch -Xclang /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/main.dir/cmake_pch.hxx.pch -Xclang -include -Xclang /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/main.dir/cmake_pch.hxx -MD -MT CMakeFiles/main.dir/src/main/main.cpp.o -MF CMakeFiles/main.dir/src/main/main.cpp.o.d -o CMakeFiles/main.dir/src/main/main.cpp.o -c /Users/clausklein/cmake/project_options/test/src/main/main.cpp
error: PCH file built from a different branch ((clang-1400.0.29.102)) than the compiler () [clang-diagnostic-error]
1 error generated.
Error while processing /Users/clausklein/cmake/project_options/test/src/main/main.cpp.
Found compiler error(s).
[7/9] Building CXX object CMakeFiles/lib2.dir/src/mylib2/lib.cpp.o
FAILED: CMakeFiles/lib2.dir/src/mylib2/lib.cpp.o 
/usr/local/Cellar/cmake/3.24.1/bin/cmake -E __run_co_compile --launcher=/usr/local/bin/ccache --tidy="/usr/local/opt/llvm/bin/clang-tidy;-extra-arg=-Wno-unknown-warning-option;-extra-arg=-std=c++20;--extra-arg-before=--driver-mode=g++" --cppcheck="/usr/local/bin/cppcheck;--template=gcc;--enable=style,performance,warning,portability;--inline-suppr;--suppress=internalAstError;--suppress=unmatchedSuppression;--inconclusive;--std=c++20" --source=/Users/clausklein/cmake/project_options/test/src/mylib2/lib.cpp -- /Applications/Xcode.app/Contents/Developer/usr/bin/g++ -DFMT_LOCALE -I/Users/clausklein/cmake/project_options/test/include -isystem /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/vcpkg_installed/x64-osx/include -isystem /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/vcpkg_installed/x64-osx/include/eigen3 -isystem /Users/clausklein/cmake/project_options/test/libs/mythirdpartylib/include -isystem /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/libs/mythirdpartylib -g -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX12.3.sdk -fcolor-diagnostics -march=native --coverage -O0 -g -fsanitize=address,undefined -Wall -Wextra -Wextra-semi -Wshadow -Wnon-virtual-dtor -Wold-style-cast -Wcast-align -Wunused -Woverloaded-virtual -Wpedantic -Wconversion -Wsign-conversion -Wnull-dereference -Wdouble-promotion -Wformat=2 -Wimplicit-fallthrough -std=c++20 -Winvalid-pch -Xclang -include-pch -Xclang /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/lib2.dir/cmake_pch.hxx.pch -Xclang -include -Xclang /Users/clausklein/cmake/project_options/test/cmake-build-test-x86_64-Debug/install/CMakeFiles/lib2.dir/cmake_pch.hxx -MD -MT CMakeFiles/lib2.dir/src/mylib2/lib.cpp.o -MF CMakeFiles/lib2.dir/src/mylib2/lib.cpp.o.d -o CMakeFiles/lib2.dir/src/mylib2/lib.cpp.o -c /Users/clausklein/cmake/project_options/test/src/mylib2/lib.cpp
error: PCH file built from a different branch ((clang-1400.0.29.102)) than the compiler () [clang-diagnostic-error]
1 error generated.
Error while processing /Users/clausklein/cmake/project_options/test/src/mylib2/lib.cpp.
Found compiler error(s).
ninja: build stopped: subcommand failed.
bash-3.2$ #

[ClausKlein]

this changes helps:

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 7739dca..b4f70da 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.16...3.21)
+cmake_minimum_required(VERSION 3.16...3.24)
 
 # set a default CXX standard used by the external tools like clang-tidy, cppcheck, etc.
 # You can later set fine-grained standards for each target using `target_compile_features`
@@ -49,16 +49,16 @@ project_options(
   ENABLE_CACHE
   ENABLE_CONAN
   # WARNINGS_AS_ERRORS
-  ENABLE_CPPCHECK
+  # ENABLE_CPPCHECK
   ENABLE_CLANG_TIDY
-  # ENABLE_INCLUDE_WHAT_YOU_USE
+  ENABLE_INCLUDE_WHAT_YOU_USE
   ENABLE_COVERAGE
-  ENABLE_PCH
-  PCH_HEADERS
-  ${PCH_HEADERS}
+  # ENABLE_PCH
+  # PCH_HEADERS
+  # ${PCH_HEADERS}
   ENABLE_DOXYGEN
-  ENABLE_INTERPROCEDURAL_OPTIMIZATION
-  ENABLE_NATIVE_OPTIMIZATION
+  # ENABLE_INTERPROCEDURAL_OPTIMIZATION
+  # ENABLE_NATIVE_OPTIMIZATION
   # ENABLE_USER_LINKER
   # ENABLE_BUILD_WITH_TIME_TRACE
   # ENABLE_UNITY

[aminya]

I have problems to build the test on my native OSX with newest apple clang:

It seems that PCH files are outdated. Clean the build directory.

[ClausKlein]

It seems that PCH files are outdated. Clean the build directory.

I do this always

[aminya]

Open a new issue. It should be reproducible in CI.