# thread-utils: build with NO_PTHREADS fails 4 messages from 2015-10-11 to 2015-10-14. Participants: Victor Leschuk, Junio C Hamano. Thread: https://gitlist.dev/t/40531 ## Victor Leschuk, 2015-10-11 12:58 Subject: thread-utils: build with NO_PTHREADS fails Message-ID: <6AE1604EE3EC5F4296C096518C6B77EE5D0FDAB9E8@mail.accesssoftek.com> URL: https://gitlist.dev/e/6AE1604EE3EC5F4296C096518C6B77EE5D0FDAB9E8%40mail.accesssoftek.com ``` Hello all, I think that no one tried it for a long time but I needed a single-threaded git version for debug purpose. I tried to build with -DNO_PTHREADS and thread-utils.c failed to compile. In brief the situation is the following: in header file we have something like that: #ifndef NO_PTHREAD extern int online_cpus(void); #else #define online_cpus() 1 #endif // NO_PTHREAD and in *.c file: int online_cpus(void) { // ... } So the compilation fails with: test.c:3:21: error: macro "online_cpus" passed 1 arguments, but takes just 0 int online_cpus(void) That's a tiny issue, but maybe we could apply a straight-forward solution (see attached diff)? If you agree I'll prepare a properly-formatted [PATCH] submit. -- Best Regards, Victor diff --git a/thread-utils.c b/thread-utils.c index a2135e0..f3e90fb 100644 --- a/thread-utils.c +++ b/thread-utils.c @@ -20,6 +20,7 @@ int online_cpus(void) { +#ifndef NO_PTHREADS #ifdef _SC_NPROCESSORS_ONLN long ncpus; #endif @@ -58,11 +59,13 @@ int online_cpus(void) return (int)ncpus; #endif +#endif return 1; } int init_recursive_mutex(pthread_mutex_t *m) { +#ifndef NO_PTHREADS pthread_mutexattr_t a; int ret; @@ -74,4 +77,7 @@ int init_recursive_mutex(pthread_mutex_t *m) pthread_mutexattr_destroy(&a); } return ret; +#else + return 0; +#endif } diff --git a/thread-utils.h b/thread-utils.h index d9a769d..6fb98c3 100644 --- a/thread-utils.h +++ b/thread-utils.h @@ -7,9 +7,5 @@ extern int online_cpus(void); extern int init_recursive_mutex(pthread_mutex_t*); -#else - -#define online_cpus() 1 - #endif #endif /* THREAD_COMPAT_H */ ``` ## Junio C Hamano, 2015-10-12 15:57 Subject: Re: thread-utils: build with NO_PTHREADS fails Message-ID: URL: https://gitlist.dev/e/xmqq7fmsnkp9.fsf%40gitster.mtv.corp.google.com In-Reply-To: <6AE1604EE3EC5F4296C096518C6B77EE5D0FDAB9E8@mail.accesssoftek.com> ``` Victor Leschuk writes: > I think that no one tried it for a long time but I needed a > single-threaded git version for debug purpose. I tried to build > with -DNO_PTHREADS and thread-utils.c failed to compile. > > In brief the situation is the following: > > in header file we have something like that: > > > #ifndef NO_PTHREAD > extern int online_cpus(void); > > #else > #define online_cpus() 1 > #endif // NO_PTHREAD > > and in *.c file: > > > int online_cpus(void) > { > // ... > } Yeah, that is obviously incorrect. The whole implementation of thread-utils.c should be enabled only under ifndef NO_PTHREADS and thread-utils.h should also privide a no-op macro for init_recursive_mutex() just like it already does for online_cpus(), which would make it unnecessary to have ifndef NO_PTHREADS sprinkled all over the place inside thread-utils.c, no? ``` ## Junio C Hamano, 2015-10-12 17:55 Subject: Re: thread-utils: build with NO_PTHREADS fails Message-ID: URL: https://gitlist.dev/e/xmqqd1wkm0om.fsf%40gitster.mtv.corp.google.com In-Reply-To: ``` Junio C Hamano writes: > Victor Leschuk writes: > >> I think that no one tried it for a long time but I needed a >> single-threaded git version for debug purpose. I tried to build >> with -DNO_PTHREADS and thread-utils.c failed to compile. >> >> In brief the situation is the following: >> >> in header file we have something like that: >> >> >> #ifndef NO_PTHREAD >> extern int online_cpus(void); >> >> #else >> #define online_cpus() 1 >> #endif // NO_PTHREAD >> >> and in *.c file: >> >> >> int online_cpus(void) >> { >> // ... >> } > > Yeah, that is obviously incorrect. > ... Well, no, I spoke too early. I do not see there is much wrong here. There is this bit in the Makefile: ifdef NO_PTHREADS BASIC_CFLAGS += -DNO_PTHREADS else BASIC_CFLAGS += $(PTHREAD_CFLAGS) EXTLIBS += $(PTHREAD_LIBS) LIB_OBJS += thread-utils.o endif The source file thread-utils.c is not compiled to thread-utils.o if you say NO_PTHREADS, and the resulting libgit.a does not of course have it. ``` ## Victor Leschuk, 2015-10-14 11:24 Subject: RE: thread-utils: build with NO_PTHREADS fails Message-ID: <6AE1604EE3EC5F4296C096518C6B77EE5D0FDAB9ED@mail.accesssoftek.com> URL: https://gitlist.dev/e/6AE1604EE3EC5F4296C096518C6B77EE5D0FDAB9ED%40mail.accesssoftek.com In-Reply-To: ``` Hello Junio, sorry that was my fault, I was building it wrong way (defined NO_PTHREADS in CFLAGS variable, not as separate make variable). Sorry for the false alarm. -- Best Regards, Victor ________________________________________ From: Junio C Hamano [jch2355@gmail.com] On Behalf Of Junio C Hamano [gitster@pobox.com] Sent: Monday, October 12, 2015 10:55 AM To: Victor Leschuk Cc: git@vger.kernel.org; vleschuk@gmail.com Subject: Re: thread-utils: build with NO_PTHREADS fails Junio C Hamano writes: > Victor Leschuk writes: > >> I think that no one tried it for a long time but I needed a >> single-threaded git version for debug purpose. I tried to build >> with -DNO_PTHREADS and thread-utils.c failed to compile. >> >> In brief the situation is the following: >> >> in header file we have something like that: >> >> >> #ifndef NO_PTHREAD >> extern int online_cpus(void); >> >> #else >> #define online_cpus() 1 >> #endif // NO_PTHREAD >> >> and in *.c file: >> >> >> int online_cpus(void) >> { >> // ... >> } > > Yeah, that is obviously incorrect. > ... Well, no, I spoke too early. I do not see there is much wrong here. There is this bit in the Makefile: ifdef NO_PTHREADS BASIC_CFLAGS += -DNO_PTHREADS else BASIC_CFLAGS += $(PTHREAD_CFLAGS) EXTLIBS += $(PTHREAD_LIBS) LIB_OBJS += thread-utils.o endif The source file thread-utils.c is not compiled to thread-utils.o if you say NO_PTHREADS, and the resulting libgit.a does not of course have it. ```