Cmake: some people build shared libtbb

[andresailer]

This Pull request:

Changes or fixes:

It fixes build errors on mac OS 26 with shared library builds of libtbb.
When STATIC is given, the rpath configuration during the linking of libThread is incorrect,

[ 57%] Linking CXX shared library ../../lib/libThread.so
/Library/Developer/CommandLineTools/usr/bin/clang++  -Wc++11-narrowing -Wsign-compare -Wsometimes-uninitialized -Wconditional-uninitialized -Wheader-guard -Warray-bounds -Wcomment -Wtautological-compare -Wstrncat-size -Wloop-analysis -Wbool-conversion -m64 -pipe -W -Wall -Woverloaded-virtual -fsigned-char -fsized-deallocation -fno-common -Qunused-arguments -pthread -stdlib=libc++ -O3 -DNDEBUG -arch arm64 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk -dynamiclib -Wl,-headerpad_max_install_names -m64 -Wl,-dead_strip_dylibs -o ../../lib/libThread.so -install_name @rpath/libThread.so CMakeFiles/Thread.dir/src/TCondition.cxx.o CMakeFiles/Thread.dir/src/TConditionImp.cxx.o CMakeFiles/Thread.dir/src/TMutex.cxx.o CMakeFiles/Thread.dir/src/TMutexImp.cxx.o CMakeFiles/Thread.dir/src/TReentrantRWLock.cxx.o CMakeFiles/Thread.dir/src/TRWLock.cxx.o CMakeFiles/Thread.dir/src/TRWMutexImp.cxx.o CMakeFiles/Thread.dir/src/TRWSpinLock.cxx.o CMakeFiles/Thread.dir/src/TSemaphore.cxx.o CMakeFiles/Thread.dir/src/TThread.cxx.o CMakeFiles/Thread.dir/src/TThreadFactory.cxx.o CMakeFiles/Thread.dir/src/TThreadImp.cxx.o CMakeFiles/Thread.dir/src/TPosixCondition.cxx.o CMakeFiles/Thread.dir/src/TPosixMutex.cxx.o CMakeFiles/Thread.dir/src/TPosixThread.cxx.o CMakeFiles/Thread.dir/src/TPosixThreadFactory.cxx.o CMakeFiles/G__Thread.dir/G__Thread.cxx.o  -Wl,-rpath,/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib ../../lib/libCore.so /Users/sftnight/build/workspace/lcg_nightly_pipeline/install/dev3/tbb/2023.1.0/arm64-mac26-clang170-opt/lib/libtbb.dylib

leading to errors later on.

[ 60%] Generating G__Net.cxx, ../../lib/Net.pcm
dyld[97986]: Library not loaded: @rpath/libtbb.12.dylib
  Referenced from: <0A33E4C2-1C88-3AEE-8935-D13F217B6639> /Volumes/build_drive/SPI-macOS-26/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libThread.so
  Reason: tried: '/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/Users/sftnight/build/workspace/lcg_nightly_pipeline/build/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib/libtbb.12.dylib' (no such file)
Subprocess aborted

After this change:

[ 55%] Linking CXX shared library ../../lib/libThread.so
cd /Users/sailer/SPI/lcgcmake/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/core/thread && /Applications/CMake.app/Contents/bin/cmake -E cmake_link_script CMakeFiles/Thread.dir/link.txt --verbose=1 /Library/Developer/CommandLineTools/usr/bin/c++  -Wc++11-narrowing -Wsign-compare -Wsometimes-uninitialized -Wconditional-uninitialized -Wheader-guard -Warray-bounds -Wcomment -Wtautological-compare -Wstrncat-size -Wloop-analysis -Wbool-conversion -m64 -pipe -W -Wall -Woverloaded-virtual -fsigned-char -fsized-deallocation -fno-common -Qunused-arguments -pthread -stdlib=libc++ -O3 -DNDEBUG -arch arm64 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk -dynamiclib -Wl,-headerpad_max_install_names -m64 -Wl,-dead_strip_dylibs -o ../../lib/libThread.so -install_name @rpath/libThread.so CMakeFiles/Thread.dir/src/TCondition.cxx
.o CMakeFiles/Thread.dir/src/TConditionImp.cxx.o CMakeFiles/Thread.dir/src/TMutex.cxx.o CMakeFiles/Thread.dir/src/TMutexImp.cxx.o CMakeFiles/Thread.dir/src/TReentrantRWLock.cxx.o CMakeFiles/Thread.dir/src/TRWLock.
cxx.o CMakeFiles/Thread.dir/src/TRWMutexImp.cxx.o CMakeFiles/Thread.dir/src/TRWSpinLock.cxx.o CMakeFiles/Thread.dir/src/TSemaphore.cxx.o CMakeFiles/Thread.dir/src/TThread.cxx.o CMakeFiles/Thread.dir/src/TThreadFactory.cxx.o CMakeFiles/Thread.dir/src/TThreadImp.cxx.o CMakeFiles/Thread.dir/src/TPosixCondition.cxx.o CMakeFiles/Thread.dir/src/TPosixMutex.cxx.o CMakeFiles/Thread.dir/src/TPosixThread.cxx.o CMakeFiles/Thread.dir/src/TPosixThreadFactory.cxx.o CMakeFiles/G__Thread.dir/G__Thread.cxx.o  -Wl,-rpath,/Users/sailer/SPI/lcgcmake/projects/ROOT-c050cbde/src/ROOT-c050cbde-build/lib -Wl,-rpath,/Users/sailer/SPI/install/dev3/tbb/2023.1.0/arm64-mac26-clang170-opt/lib ../../lib/libCore.so /Users/sailer/SPI/install/dev3/tbb/2023.1.0/arm64-mac26-clang170-opt/lib/libtbb.dylib

Note the rpath setting before libtbb.dylib here

Checklist:

• tested changes locally for macos 26

[github-actions]

Test Results

     6 files       6 suites   23h 3m 28s ⏱️
 3 807 tests  3 802 ✅ 5 💤 0 ❌
20 993 runs  20 993 ✅ 0 💤 0 ❌

Results for commit 4887ff4.

♻️ This comment has been updated with latest results.

[pcanal]

Side note: this may (or may not) also be beneficial on Windows (CMake documentation says "[using] UNKOWN ... This is especially useful on Windows where a static library and a DLL's import library both have the same file extension.")

[pcanal]

@andresailer We currently do not support merging in local branches named master. All the CI build fails with:

Fatal error:  The branch name in the fork and the base-ref are both called master. This is not supported. Please change the name of the branch in the forked repository.

[andresailer]

Replaced by #23089

Since Github utterly failed, I couldn't replace it until end of business yesterday