[Chapel Merge] Fix problem with dyno builds on Mac OS X with LLVM

Branch: refs/heads/main
Revision: 6974cfe
Author: mppf
Link: Fix problem with dyno builds on Mac OS X with LLVM by mppf · Pull Request #19746 · chapel-lang/chapel · GitHub
Log Message:

Merge pull request #19746 from mppf/fix-cmake-sdkroot

Fix problem with dyno builds on Mac OS X with LLVM

We were observing problems with 'make test-dyno' when CHPL_LLVM=system
on Mac OS X with Homebrew cmake and llvm.

The cmake build tries to gather the command line arguments
from chplenv but sometimes these include -isysroot, but cmake wants to
have its own variable to set that. This PR just adjusts the Makefiles to
configure cmake's sdkroot to match whatever -isysroot our chplenv scripts
have figured out. That way, if cmake adds a flag for it in addition, it
is OK, because everything is consistent.

Reviewed by @benharsh - thanks!

Modified Files:
M compiler/dyno/Makefile.help

M util/chplenv/chpl_llvm.py

Compare: https://github.com/chapel-lang/chapel/compare/a3f8b7e010ba...6974cfed5ea5