[External][SPEC2000] Introspect -zmuldefs linker option before use.

[Meinersbur]

Summary

D95276 unconditionally added the -zmuldefs which is not supported by all linkers. Check whether the compiler/linker accept the flags before using.

[fhahn]

LGTM, thanks!

I also verified this fixes the issues on Darwin platforms locally.

[Meinersbur]

• Put check_c_source_compiles into function to keep CMAKE_REQUIRED_LINK_OPTIONS in scope
• LINKER_MULTIDEF_FLAGS typo

External/SPEC/CINT2000/186.crafty/CMakeLists.txt

 if(LONG64_TYPE_SIZE EQUAL 8)
   list(APPEND CPPFLAGS -DLONG_HAS_64BITS)
 endif()
 check_type_size("long long" LONG_LONG_TYPE_SIZE BUILTIN_TYPES_ONLY)
 if(LONG_LONG_TYPE_SIZE GREATER 7)
   list(APPEND CPPFLAGS -DHAS_LONGLONG)
 endif()
 
-list(APPEND LDFLAGS -Wl,-zmuldefs)
+list(APPEND LDFLAGS ${LD_MULTIDEF_FLAG})
 
 set(SourceNames
   attacks.c
   boolean.c
   draw.c
   drawn.c
   edit.c
   enprise.c

External/SPEC/CINT2000/300.twolf/CMakeLists.txt

 list(APPEND CPPFLAGS -DHAVE_SIGNED_CHAR)
 list(APPEND LDFLAGS -lm)
-list(APPEND LDFLAGS -Wl,-zmuldefs)
+list(APPEND LDFLAGS ${LD_MULTIDEF_FLAG})
 list(APPEND CFLAGS -Wno-return-type)
 
 macro(test_input run_type)
   llvm_test_run(RUN_TYPE ${run_type}
     WORKDIR ${CMAKE_CURRENT_BINARY_DIR}/data/${run_type}/input
     ${run_type} > ${run_type}.stdout
   )
   foreach(file IN ITEMS ${run_type}.twf ${run_type}.pl2 ${run_type}.sav ${run_type}.pl1 ${run_type}.pl1 ${run_type}.pin ${run_type}.stdout ${run_type}.sv2 ${run_type}.out)

External/SPEC/SpecCPU2000.cmake

 include(External)
+include(CheckCSourceCompiles)
 llvm_externals_find(TEST_SUITE_SPEC2000_ROOT "speccpu2000" "SPEC CPU2000")
 if(TEST_SUITE_SPEC2000_ROOT)
   # SPEC supports three "run types": ref, train and test
   if(NOT TEST_SUITE_RUN_TYPE STREQUAL "train" AND
      NOT TEST_SUITE_RUN_TYPE STREQUAL "test" AND
      NOT TEST_SUITE_RUN_TYPE STREQUAL "ref")
     message(FATAL_ERROR
             "TEST_SUITE_RUN_TYPE must be 'train', 'test' or 'ref' for SPEC")
")
 
   function(llvm_test_data_spec target)
     llvm_test_data(${target} SOURCE_DIR ${BENCHMARK_DIR} ${ARGN})
   endfunction()
 
   function(llvm_test_data_spec_default target)
     llvm_test_data_spec(${target} data)
   endfunction()
+
+  function(check_supports_zmuldefs)
+    # Does not check whether the option has an effect.
+    # -z options are usually ignored if the particular option.
+    # Alternative option is --allow-multiple-definition
+    set(CMAKE_REQUIRED_LINK_OPTIONS "-Wl,-zmuldefs")
+    check_c_source_compiles("int main() { return 0; };" LINKER_SUPPORTS_ZMULDEFS)
+  endfunction()
+
+  check_supports_zmuldefs()
+  set(LD_MULTIDEF_FLAG)
+  if(LINKER_SUPPORTS_ZMULDEFS)
+    set(LD_MULTIDEF_FLAG "-Wl,-zmuldefs")
+  endif()
 endif()