try_compile: Restore expansion of ;-list in COMPILE_DEFINITIONS
The quoting added by commit 8c5221fb from !2716 (merged)
broke the case that the
COMPILE_DEFINITIONS value contains a
Without the quoting the
; would be generated literally in an unquoted
argument in the test
CMakeLists.txt file and would then be expanded.
With quoting the
; is preserved, which is not the old behavior.
Fix this by expanding the
;-list ahead of time. Add test cases for
behavior with both
This was noticed with the PGI compiler where we set
CMAKE_CXX*_STANDARD_COMPILE_OPTION to values like
symptom had also been observed while preparing !2894 (merged) but was not recognized at the time
as a regression. Revert the workaround added by that commit.
Fixes: #18919 (closed)