[test-suite][WIP] Allow GCC to build test suite

[lenary]

Summary

The (CMake-based) test suite has errors if you try to build it with
GCC. It seems useful to be able to test GCC with the relevant parts of the LLVM
test suite, just as it is relevant to run clang against the GCC torture suite.

This patch is an initial attempt to fix any build configuration issues
associated with running the lnt test suite with GCC.

[lenary]

There are still failures I need to address in:

• MultiSource/MultiSource.Benchmarks.Trimaran.enc-pc1/enc-pc1.test (this is very odd, some numbers are printed as 2048 less than they should be, usually turning them negative)
• MicroBenchmarks/MicroBenchmarks.XRay.FDRMode/fdrmode-bench.test (not investigated)
• MicroBenchmarks/MicroBenchmarks.XRay.ReturnReference/retref-bench.test (not investigated)

CMakeLists.txt

 # directory where they will be picked up automatically. Alternatively you may
 # manually specify directories to include test-suites at external locations
 # and to leave out some of the default ones.
 if(NOT TEST_SUITE_SUBDIRS)
   file(GLOB sub_cmakelists RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} */CMakeLists.txt)
   set(TEST_SUITE_SUBDIRS "")
   foreach(entry ${sub_cmakelists})
     get_filename_component(subdir ${entry} DIRECTORY)
-   # Exclude tools and CTMark from default list
-    if(NOT ${subdir} STREQUAL tools AND NOT ${subdir} STREQUAL CTMark)
-      list(APPEND TEST_SUITE_SUBDIRS ${subdir})
-    endif()
   endforeach()
+  # Exclude tools and CTMark from default list
+  list(REMOVE_ITEM TEST_SUITE_SUBDIRS tools CTMark)
+  # Exclude Bitcode tests on GCC
+  if(${CMAKE_C_COMPILR_ID} STREQUAL "GNU")
+    list(REMOVE_ITEM TEST_SUITE_SUBDIRS Bitcode)
+  endif()
   set(TEST_SUITE_SUBDIRS "${TEST_SUITE_SUBDIRS}")
 endif()
 set(TEST_SUITE_SUBDIRS "${TEST_SUITE_SUBDIRS}" CACHE STRING
     "Semicolon separated list of directories with CMakeLists.txt to include")
 
 foreach(subdir ${TEST_SUITE_SUBDIRS})
   # When we add subdirs outside the toplevel source directory then we have to
   # make up a directory to use for the builddir.

MultiSource/Benchmarks/7zip/CMakeLists.txt

 set(RUN_OPTIONS b)
 list(APPEND CFLAGS -DBREAK_HANDLER -DUNICODE -D_UNICODE -I${CMAKE_CURRENT_SOURCE_DIR}/C -I${CMAKE_CURRENT_SOURCE_DIR}/CPP/myWindows -I${CMAKE_CURRENT_SOURCE_DIR}/CPP/include_windows -I${CMAKE_CURRENT_SOURCE_DIR}/CPP -I. -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -DNDEBUG -D_REENTRANT -DENV_UNIX -D_7ZIP_LARGE_PAGES -pthread)
-list(APPEND CXXFLAGS -Wno-error=c++11-narrowing -DBREAK_HANDLER -DUNICODE -D_UNICODE -I${CMAKE_CURRENT_SOURCE_DIR}/C -I${CMAKE_CURRENT_SOURCE_DIR}/CPP/myWindows -I${CMAKE_CURRENT_SOURCE_DIR}/CPP/include_windows -I${CMAKE_CURRENT_SOURCE_DIR}/CPP -I. -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -DNDEBUG -D_REENTRANT -DENV_UNIX -D_7ZIP_LARGE_PAGES -pthread)
+if(NOT ${CMAKE_C_COMPILR_ID} STREQUAL "GNU")
+list(APPEND CXXFLAGS -Wno-error=c++11-narrowing)
+endif()
+list(APPEND CXXFLAGS -DBREAK_HANDLER -DUNICODE -D_UNICODE -I${CMAKE_CURRENT_SOURCE_DIR}/C -I${CMAKE_CURRENT_SOURCE_DIR}/CPP/myWindows -I${CMAKE_CURRENT_SOURCE_DIR}/CPP/include_windows -I${CMAKE_CURRENT_SOURCE_DIR}/CPP -I. -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -DNDEBUG -D_REENTRANT -DENV_UNIX -D_7ZIP_LARGE_PAGES -pthread)
 list(APPEND LDFLAGS -lstdc++ -pthread)
 set(NO_REFERENCE_OUTPUT 1)
 llvm_multisource(7zip-benchmark
   CPP/myWindows/myGetTickCount.cpp
   CPP/myWindows/wine_date_and_time.cpp
   CPP/myWindows/myAddExeFlag.cpp
   CPP/myWindows/mySplitCommandLine.cpp
   CPP/7zip/UI/Console/BenchCon.cpp