[test-suite] Fix Xcode SDK cmake cache for benchmarks using re_comp

[thegameg]

Summary

cmake thinks it found re_comp after r317058.

Test affected:

• MultiSource/Benchmarks/Prolangs-C/plot2fig
• MultiSource/Benchmarks/Prolangs-C/archie-client

[MatzeB]

LGTM

test-suite/trunk/cmake/caches/util/xcode_sdk.cmake

DYLD_LIBRARY_PATH=\"${COMPILER_DIR}/../lib:$DYLD_LIBRARY_PATH\" ${SDK_TOOL_BIN} \"$@\"
   create_shim(CMAKE_NM nm)
   create_shim(CMAKE_RANLIB ranlib)
   create_shim(CMAKE_STRIP strip)
 
   # Skip linking in cmake compiler tests, as the cmake won't pass the -B flags
   # required to pick up the correct linker to the early compiler tests. However
   # it does have an option to not link in the early tests.
   set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY CACHE STRING "")
+
+  # Some benchmarks check for the function re_comp by using
+  # check_function_exists. This function is not available in any Xcode SDK, and
+  # the check returns YES with custom built compilers when we cross-compile,
+  # because of "CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY" explained just
+  # above. We work around that by forcing it to NO.
+  set(HAVE_RE_COMP CACHE BOOL NO)
 else()
   # Search and use compiler coming with the SDK.
   # Note that we do not search CMAKE_CXX_COMPILER here. cmake will try
   # `${CMAKE_C_COMPILER}++` and use that if available.
   xcrun_find_update_cache(CMAKE_AR ar)
   xcrun_find_update_cache(CMAKE_NM nm)
   xcrun_find_update_cache(CMAKE_C_COMPILER clang)
   xcrun_find_update_cache(CMAKE_RANLIB ranlib)