External Issue: Chapel 1.26.0: building with GCC and CHPL_LLVM=bundled fails to find clang binary

19791, "devreal", "Chapel 1.26.0: building with GCC and CHPL_LLVM=bundled fails to find clang binary", "2022-05-10T23:01:08Z"

Summary of Problem

Building with GCC and setting CHPL_LLVM=bundled, make fails to find the clang binary, looking for third-party/llvm/install/linux64-x86_64-clang/bin/clang instead of third-party/llvm/install/linux64-x86_64-gnu/bin/clang. Notice the difference between linux64-x86_64-clang and linux64-x86_64-gnu.

Steps to Reproduce

Source Code:

Chapel release 1.26.0

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Compile command:

$ export CHPL_LLVM=bundled
$ ./configure --chpl-home=/path/to/opt/chapel-1.26.0
$ make -j16
...
cd standard/gen/linux64-x86_64-llvm && python3 /path/to/src/chapel-1.26.0/util/config/make_sys_basic_types.py ChapelSysCTypes.chpl
/bin/sh: /path/to/src/chapel-1.26.0/third-party/llvm/install/linux64-x86_64-clang/bin/clang: No such file or directory
ERROR: Found 0 max values, but 18 types were expected.

Looking for the clang binary, it's there but in a different directory:

$ find . -name clang
./third-party/llvm/install/linux64-x86_64-gnu/lib/clang
./third-party/llvm/install/linux64-x86_64-gnu/lib/cmake/clang
./third-party/llvm/install/linux64-x86_64-gnu/share/clang
./third-party/llvm/install/linux64-x86_64-gnu/include/clang
./third-party/llvm/install/linux64-x86_64-gnu/bin/clang
...