builtins test: Move clear_cache_test.c from a mprotect()ed global to a mmap()ed variable

ld64 in the macOS 10.15 SDK gives __DATA a maxprot of 3, meaning it
can't be made executable at runtime by default.

Change clear_cache_test.c to use mmap()ed data that's mapped as writable
and executable from the beginning, instead of trying to mprotect()ing a
__DATA variable as executable. This fixes the test on macOS with the
10.15 SDK.


Differential Revision: https://reviews.llvm.org/D67929

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@372849 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed