Removing the 'd' debug postfix broke the CMake workflow

[stilllman]

Describe the bug

Removing the 'd' suffix for debug libs broke the CMake workflow.

The FindGTest.cmake of cmake expects the debug libraries of gtest to have this suffix : https://github.com/Kitware/CMake/blob/master/Modules/FindGTest.cmake#L248

Similarly, the export of targets is now broken, if you build both the Release and the Debug version and install them at the same location, you end up with the two generated config files referencing the same libraries (which have been overwritten by the latest configuration built).

Steps to reproduce the bug

mkdir gtest && cd gtest
git clone git@github.com:google/googletest.git
mkdir build-debug build-release install
cmake -S googletest/ -B build-debug/ -DCMAKE_BUILD_TYPE=Debug -DCMAKE_INSTALL_PREFIX=$PWD/install
cmake --build build-debug
cmake --build build-debug -- install
cmake -S googletest/ -B build-release/ -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=$PWD/install
cmake --build build-release
cmake --build build-release -- install
grep IMPORTED_LOCATION install/lib64/cmake/GTest/GTest*.cmake

Does the bug persist in the most recent commit?

Yes

What operating system and version are you using?

Linux, Windows, Mac

What compiler and version are you using?

Irrelevant

What build system are you using?

CMake, version irrelevant

[stilllman]

Note that @Neumann-A raised the issue before this was merged, in #3453, with what seems to be the actual correct solution: generate a .pc file with the appropriate suffix

[B3ret]

Also ran into this.
Until this is fixed, a workaround is to cmake-configure with the CMAKE_DEBUG_PREFIX flag, that will be used for all targets:

cmake .... -DCMAKE_DEBUG_POSTFIX="d" ...

[phetdam]

This is still a problem with the HEAD of main, currently 79219e2, and with the v1.15.0 release tag as well.

The -DCMAKE_DEBUG_POSTFIX=d addition to the CMake configure step works and is very useful on Windows where there is more than one C runtime library and the debug/release libraries are not ABI compatible. In this case, it can be desirable to have the Debug and Release configs both installed into the same install root, each linking against appropriate C runtimes. Therefore, having a suffix indicating which libraries are the debug ones becomes quite important.

However, even with "debug" builds without any compiler or linker optimization, one can still use MSVC_RUNTIME_LIBRARY to force use of a particular C runtime. In that case, just building the Release config with -Dgtest_force_shared_crt=ON would be sufficient, so I'm not sure if introducing extra logic into the CMake build to provide a sensible default would help much.