Unable to build master branch on Mac OS due to use of malloc and memalign()

[RulerOf]

Attempting to build on Mac OS fails because we don't have malloc.h on the platform:

andrewbobulsky ~/Projects/personal/build-stratagus
% CXX=$(brew --prefix)/bin/g++-11 CC=$(brew --prefix)/bin/gcc-11 cmake ../stratagus -DENABLE_DEV=ON
-- The C compiler identification is GNU 11.3.0
-- The CXX compiler identification is GNU 11.3.0
<snip>
==================================
-- Configuring done
-- Generating done
-- Build files have been written to: /Users/andrewbobulsky/Projects/personal/build-stratagus
6s andrewbobulsky ~/Projects/personal/build-stratagus
% make -j$(nproc)
[  0%] Building CXX object CMakeFiles/genversion.dir/tools/genversion.cpp.o
<snip>
[ 82%] Building CXX object CMakeFiles/stratagus.dir/src/ui/button_checks.cpp.o
/Users/andrewbobulsky/Projects/personal/stratagus/src/stratagus/util.cpp:44:10: fatal error: malloc.h: No such file or directory
   44 | #include <malloc.h>
      |          ^~~~~~~~~~
compilation terminated.
make[2]: *** [CMakeFiles/stratagus.dir/src/stratagus/util.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [CMakeFiles/stratagus.dir/all] Error 2
make: *** [all] Error 2

I can use #ifndef to avoid loading malloc.h and letting stdlib.h do the job:

...but we fail later because memalign() is not supported:

[ 83%] Building CXX object CMakeFiles/stratagus.dir/src/ui/icons.cpp.o
/Users/andrewbobulsky/Projects/personal/stratagus/src/stratagus/util.cpp: In function 'void* aligned_malloc(size_t, size_t)':
/Users/andrewbobulsky/Projects/personal/stratagus/src/stratagus/util.cpp:640:16: error: 'memalign' was not declared in this scope
  640 |         return memalign(alignment, size);
      |                ^~~~~~~~
[ 84%] Building CXX object CMakeFiles/stratagus.dir/src/ui/interface.cpp.o
[ 84%] Building CXX object CMakeFiles/stratagus.dir/src/ui/mainscr.cpp.o
make[2]: *** [CMakeFiles/stratagus.dir/src/stratagus/util.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
[ 85%] Building CXX object CMakeFiles/stratagus.dir/src/ui/uibuttons_proc.cpp.o
make[1]: *** [CMakeFiles/stratagus.dir/all] Error 2
make: *** [all] Error 2

I did try briefly to comprehend what the function is doing but I'm not familiar enough with CPU plumbing to resolve the problem.

Stackoverflow suggests the use of posix_memalign(). It seemed reasonable to stuff it in here

stratagus/src/stratagus/util.cpp

Lines 631 to 640 in c2706c2

	void *aligned_malloc(size_t alignment, size_t size)
	{
	#ifdef WIN32
	return _aligned_malloc(size, alignment);
	#elif _ISOC11_SOURCE
	return aligned_alloc(alignment, size);
	#else
	return memalign(alignment, size);
	#endif
	}

and my wildest guess is something like this might do the trick:

void *aligned_malloc(size_t alignment, size_t size)
{
#ifdef WIN32
	return _aligned_malloc(size, alignment);
#elif _ISOC11_SOURCE
	return aligned_alloc(alignment, size);
#elif __APPLE__
	return posix_memalign(?????????, alignment, size);
#else
	return memalign(alignment, size);
#endif
}

But I couldn't even begin to tell ya what goes in the first arg of the function ¯\_(ツ)_/¯

[RulerOf]

Just confirming this still happens on the most-recent updates:

[ 82%] Building CXX object CMakeFiles/stratagus.dir/src/ui/botpanel.cpp.o
/Users/andrewbobulsky/Projects/personal/stratagus/src/stratagus/util.cpp:44:10: fatal error: malloc.h: No such file or directory
   44 | #include <malloc.h>
      |          ^~~~~~~~~~
compilation terminated.
make[2]: *** [CMakeFiles/stratagus.dir/src/stratagus/util.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [CMakeFiles/stratagus.dir/all] Error 2
make: *** [all] Error 2
(2) 17s andrewbobulsky ~/Projects/personal/build-stratagus
% git -C ../stratagus rev-parse HEAD
361ee0b05c9cb28a827a0385c36dadb8b132434b

[timfel]

Hi, thanks for the report. Unfortunately none of the devs have macs anymore, so we cannot really test. If you figure it out, I would be very happy to merge a fix :)

[timfel]

Ah, just remembered, the usage of memalign is a performance optimization, so you might get away with simply using malloc and free in those functions

[timfel]

I got access to a mac over the weekend, and figured I'd quickly take a look ;)