> in some MinGW64 header files? Easily eliminated:
martind@sirius:~/tmp/svensson-2023-06-08$ cat make.c #include <stdint.h> intptr_t _get_osfhandle(int); typedef void* HANDLE; HANDLE fn() { return (HANDLE)_get_osfhandle(0); } martind@sirius:~/tmp/svensson-2023-06-08$ gcc -c -Wbad-function-cast make.c make.c: In function ‘fn’: make.c:7:10: warning: cast from function call of type ‘intptr_t {aka long int}’ to non-matching type ‘void *’ [-Wbad-function-cast] return (HANDLE)_get_osfhandle(0); ^ martind@sirius:~/tmp/svensson-2023-06-08$ That's gcc-6.3, but it's much the same in every version I tested from gcc-4.4 to gcc-10. A random version's man page, https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html, explains the flag as to: > Warn when a function call is cast to a non-matching type. For example, warn > if a call to a function returning an integer type is cast to a pointer type. I fear they mean exactly what they say there. So, while you might call it a mistake, I don't think it's an accident. https://stackoverflow.com/a/35308713/18096 has some explanation of why it might sometimes be useful... and how it could be sidestepped by a change to Gnu Make, like our new friend wished for.