Fix compilation of googletest with MinGW using Win32 threads

[ilmagico]

Fixes #708.

Allows to compile googletest with MinGW when pthreads support is disabled.
Also, the cmake build automatically disables pthreads supportwhen MinGW is used.

Tested on Win7, with MinGW 4.8.1, cmake 3.5.0. All tests pass, except for gmock-matchers_test that fails because of a limitation of MinGW not being able to handle "too many sections", most likely unrelated to the issue being addressed here (see below).

Unfortunately, I am not able to (legally) test with MSVC compiler, anybody please help test.

Also tested on Linux, although I expect no differences.

cmake command line used for testing:
cmake -G "MinGW Makefiles" -Dgtest_build_samples=ON -Dgmock_build_samples=ON -Dgtest_build_tests=ON -Dgmock_build_tests=ON ..

MinGW "too many section" issue:

c:/mingw-2/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/as.exe: CMakeFiles\gmock-matchers_test.dir\test\gmock-matchers_test.cc.obj: too many sections (43319)
C:\Users\ilmagico\AppData\Local\Temp\cc4PXqrl.s: Assembler messages:
C:\Users\ilmagico\AppData\Local\Temp\cc4PXqrl.s: Fatal error: can't write CMakeFiles\gmock-matchers_test.dir\test\gmock-matchers_test.cc.obj: File too big
c:/mingw-2/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/as.exe: CMakeFiles\gmock-matchers_test.dir\test\gmock-matchers_test.cc.obj: too many sections (43319)
C:\Users\ilmagico\AppData\Local\Temp\cc4PXqrl.s: Fatal error: can't close CMakeFiles\gmock-matchers_test.dir\test\gmock-matchers_test.cc.obj: File too big

and (after using make --keep-going)

98% tests passed, 1 tests failed out of 59

Total Test time (real) =  26.45 sec

The following tests FAILED:
          9 - gmock-matchers_test (Not Run)

Apparently this limitation is lifted in recent versions of MinGW64 (when compiling in 64-bit mode), if I get a chance I'll try that too.

[orgads]

This breaks compilation with MinGW 5.2.0.

[dneto0]

Same for me. This breaks compilation on Linux with MinGW 4.8.2

gtest-port.cc:242:45: error: cannot convert ‘CRITICAL_SECTION* {aka _RTL_CRITICAL_SECTION*}’ to ‘GTEST_CRITICAL_SECTION* {aka _CRITICAL_SECTION*}’ in initialization
       critical_section_(new CRITICAL_SECTION) {

[KindDragon]

Fix this in PR #856, but a lot of test still failing with MinGW

[orgads]

Tested with MSVC. All compiles. With recent MinGW it is broken though.

[andoks]

Seems to work with MSVC 2010. But fails for me when trying to build with MinGW (g++ -v: gcc version 4.9.2 (i686-posix-dwarf-rev1, Built by MinGW-W64 project) )

cmake -G "MSYS Makefiles" -H. -B_builds -DCMAKE_INSTALL_PREFIX=$(pwd)/_install
cmake --build _builds/ --target install

First error is:

googletest-fix-mingw-threads/googletest/src/gtest-port.cc:242:45: error: cannot convert 'CRITICAL_SECTION* {aka RTL_CRITICAL_SECTION}' to 'GTEST_CRITICAL_SECTION_ {aka CRITICAL_SECTION*}' in initialization
critical_section(new CRITICAL_SECTION) {

[andoks]

I believe I was experiencing the same issue late last year (see issue #606 and PR #608).

As far as I can understand the original issue is that commit a634042 introduced internal testing of GTests' use of threads, and tried to disable pthreads on MinGW but failed.

I tried building GTest master with something similar to PR #608 above, and disabling pthreads on a top-level makes the build work on MinGW.

Maybe the best way to go about it would be to first properly disable pthreads, then implement the threading testing when building with MinGW?

[BillyDonahue]

This looks good. Thanks.

[ArekPiekarz]

This merge broke compilation on Windows 10 x64 with MinGW 5.3 x32. It comes bundled with Qt 5.7 SDK. Now I get errors like this:

In file included from ......\lib\googletest\googletest\src\gtest-all.cc:45:0:
D:/dev/lib/googletest/googletest/src/gtest-port.cc: In constructor 'testing::internal::Mutex::Mutex()':
D:/dev/lib/googletest/googletest/src/gtest-port.cc:242:45: error: cannot convert 'CRITICAL_SECTION* {aka RTL_CRITICAL_SECTION}' to 'GTEST_CRITICAL_SECTION_ {aka CRITICAL_SECTION*}' in initialization
critical_section(new CRITICAL_SECTION) {
^
D:/dev/lib/googletest/googletest/src/gtest-port.cc:243:48: error: cannot convert 'GTEST_CRITICAL_SECTION* {aka CRITICAL_SECTION}' to 'LPCRITICAL_SECTION {aka RTL_CRITICAL_SECTION}' for argument '1' to 'void InitializeCriticalSection(LPCRITICAL_SECTION)'
::InitializeCriticalSection(critical_section_);
^
In file included from D:/dev/lib/googletest/googletest/include/gtest/internal/gtest-internal.h:40:0,
from D:/dev/lib/googletest/googletest/include/gtest/gtest.h:58,
from ......\lib\googletest\googletest\src\gtest-all.cc:39:
D:/dev/lib/googletest/googletest/include/gtest/internal/gtest-port.h:402:16: note: class type 'GTEST_CRITICAL_SECTION {aka _CRITICAL_SECTION}' is incomplete
typedef struct CRITICAL_SECTION GTEST_CRITICAL_SECTION;
^
In file included from ......\lib\googletest\googletest\src\gtest-all.cc:45:0:
D:/dev/lib/googletest/googletest/src/gtest-port.cc: In destructor 'testing::internal::Mutex::~Mutex()':
D:/dev/lib/googletest/googletest/src/gtest-port.cc:253:46: error: cannot convert 'GTEST_CRITICAL_SECTION* {aka CRITICAL_SECTION}' to 'LPCRITICAL_SECTION {aka RTL_CRITICAL_SECTION}' for argument '1' to 'void DeleteCriticalSection(LPCRITICAL_SECTION)'
::DeleteCriticalSection(critical_section);
^