From: Johannes Sixt Date: Tue, 01 Mar 2016 19:34:58 GMT Subject: Re: [PATCH v2] Mark win32's pthread_exit() as NORETURN Message-ID: <56D5EEE2.3080100@kdbg.org> In-Reply-To: Am 01.03.2016 um 15:13 schrieb Johannes Schindelin: > The pthread_exit() function is not expected to return. Ever. On Windows, > we call ExitThread() whose documentation claims: "This function does not > return a value.": > > https://msdn.microsoft.com/en-us/library/windows/desktop/ms682659 This is misleading: MSDN marks all functions declared void as "does not return a value," for example, look at EnterCriticalSection: https://msdn.microsoft.com/en-us/library/windows/desktop/ms682608 For this reason, I actually prefer your version 1 patch without the explanation. > > Pointed out by Jeff King. > > Signed-off-by: Johannes Schindelin > --- > > Relative to v1, only the commit message changed (to clarify that > ExitThread() indeed never returns). > > compat/win32/pthread.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/compat/win32/pthread.h b/compat/win32/pthread.h > index 20b35a2..148db60 100644 > --- a/compat/win32/pthread.h > +++ b/compat/win32/pthread.h > @@ -78,7 +78,7 @@ extern int win32_pthread_join(pthread_t *thread, void **value_ptr); > #define pthread_equal(t1, t2) ((t1).tid == (t2).tid) > extern pthread_t pthread_self(void); > > -static inline int pthread_exit(void *ret) > +static inline int NORETURN pthread_exit(void *ret) I would have written it as #ifdef __GNUC__ __attribute__((__noreturn__)) #endif static inline int pthread_exit(void *ret) ... but I can live with your version as long as it compiles. Your solution is pragmatic: NORETURN is defined in git-compat-util.h, and by using it here, we depend on that pthread.h is included sufficiently late that the macro is available at this point. The instance in compat/nedmalloc/malloc.c.h is bracketed with #ifndef WIN32 so that it is not compiled on Windows, all other instances are after git-compat-util.h or cache.h or in headers that are to be included only after git-compat-util.h or cache.h per convention. Looks like we are safe. > { > ExitThread((DWORD)(intptr_t)ret); > } >