Warnings when cross-compiling

[fatduckling]

Hi I'm using mingw compiler on Debian to cross-compile juice to windows. I'm seeing the following warnings:

...
[ 85%] Building C object CMakeFiles/juice.dir/src/turn.c.obj
[ 90%] Building C object CMakeFiles/juice.dir/src/udp.c.obj
[ 95%] Building C object CMakeFiles/juice.dir/src/timestamp.c.obj
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/log.c:10:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:272: CMakeFiles/juice.dir/src/log.c.obj] Error 1
make[2]: *** Waiting for unfinished jobs....
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/random.c:11:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:287: CMakeFiles/juice.dir/src/random.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.h:14,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.c:9:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:137: CMakeFiles/juice.dir/src/conn.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/udp.c:13:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:362: CMakeFiles/juice.dir/src/udp.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.h:14,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn_poll.h:13,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn_poll.c:9:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:152: CMakeFiles/juice.dir/src/conn_poll.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.h:14,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn_thread.h:13,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn_thread.c:9:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:167: CMakeFiles/juice.dir/src/conn_thread.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.h:14,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn_mux.h:13,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn_mux.c:9:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:182: CMakeFiles/juice.dir/src/conn_mux.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.h:14,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/agent.h:13,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/juice.c:11:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:257: CMakeFiles/juice.dir/src/juice.c.obj] Error 1
In file included from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/conn.h:14,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/agent.h:13,
                 from /tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/agent.c:9:
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h: In function 'thread_set_name_self':
/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/src/thread.h:114:29: error: cast between incompatible function types from 'FARPROC' {aka 'long long int (*)()'} to 'HRESULT (*)(void *, const WCHAR *)' {aka 'long int (*)(void *, const short unsigned int *)'} [-Werror=cast-function-type]
  114 |                             (pfnSetThreadDescription)GetProcAddress(kernel32, "SetThreadDescription");
      |                             ^
cc1: all warnings being treated as errors
make[2]: *** [CMakeFiles/juice.dir/build.make:92: CMakeFiles/juice.dir/src/agent.c.obj] Error 1
make[2]: Leaving directory '/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/build_WINDOWS_X86_64'
make[1]: *** [CMakeFiles/Makefile2:84: CMakeFiles/juice.dir/all] Error 2
make[1]: Leaving directory '/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/build_WINDOWS_X86_64'
make: *** [Makefile:136: all] Error 2
make: Leaving directory '/tmp/93351f1ab8597e75f5032a550fef65e991d8a4bf/build_WINDOWS_X86_64'

I've tried Android, iOS, OSX cross-compilers on Debian and they didn't produce these warnings. It's only for Windows cross-compilation they're appearing.

Thanks

[paullouisageneau]

This is expected, you need to perform that cast when invoking GetProcAddress() on Windows. The best you can do here is ignore the warning. If you want you can disable it in CMakeLists.txt to be able to compile with warnings as errors.