On Sat, Apr 20, 2024 at 02:49:38PM +0200, ???? ??????? wrote: > ??, 11 ???. 2024 ?. ? 21:05, Willy Tarreau <w...@1wt.eu>: > > > Hi Ilya, > > > > On Thu, Apr 11, 2024 at 08:27:39PM +0200, ???? ??????? wrote: > > > do you know maybe how this was supposed to work ? > > > haproxy/Makefile at master · haproxy/haproxy (github.com) > > > <https://github.com/haproxy/haproxy/blob/master/Makefile#L499> > > > > That's this: > > > > ifneq ($(shell $(CC) $(CFLAGS) -dM -E -xc - </dev/null 2>/dev/null | > > grep -c 'LOCK_FREE.*1'),0) > > USE_LIBATOMIC = implicit > > endif > > > > It calls the compiler with the known flags and checks if for this arch, > > it's configured to require libatomic. > > > > macros has changed from 1 to 2: > > ilia@fedora:~/Downloads$ cc -dM -E -xc - </dev/null 2>/dev/null | grep LOCK > #define __GCC_ATOMIC_CHAR_LOCK_FREE 2 > #define __GCC_ATOMIC_CHAR32_T_LOCK_FREE 2 > #define __GCC_ATOMIC_BOOL_LOCK_FREE 2 > #define __GCC_ATOMIC_POINTER_LOCK_FREE 2 > #define __GCC_ATOMIC_INT_LOCK_FREE 2 > #define __GCC_ATOMIC_WCHAR_T_LOCK_FREE 2 > #define __GCC_ATOMIC_LONG_LOCK_FREE 2 > #define __GCC_ATOMIC_CHAR16_T_LOCK_FREE 2 > #define __GCC_ATOMIC_LLONG_LOCK_FREE 2 > #define __GCC_ATOMIC_SHORT_LOCK_FREE 2
This means it's always lock-free, implemented natively thus doesn't require libatomic. Value 1 means "sometimes lock-free" and implemented as a function provided by libatomic. Did the problem appear when I changed the flags in the makefile ? Maybe I accidently lost one and it's falling back to a subset of the target arch ? > the following patch works, but I'll play a bit more .... > > diff --git a/Makefile b/Makefile > index 4bd263498..370ac7ed0 100644 > --- a/Makefile > +++ b/Makefile > @@ -493,7 +493,7 @@ $(set_target_defaults) > # linking with it by default as it's not always available nor deployed > # (especially on archs which do not need it). > ifneq ($(USE_THREAD:0=),) > - ifneq ($(shell $(CC) $(OPT_CFLAGS) $(ARCH_FLAGS) $(CPU_CFLAGS) > $(STD_CFLAGS) $(WARN_CFLAGS) $(NOWARN_CFLAGS) $(ERROR_CFLAGS) $(CFLAGS) -dM > -E -xc - </dev/null 2>/dev/null | grep -c 'LOCK_FREE.*1'),0) > + ifneq ($(shell $(CC) $(OPT_CFLAGS) $(ARCH_FLAGS) $(CPU_CFLAGS) > $(STD_CFLAGS) $(WARN_CFLAGS) $(NOWARN_CFLAGS) $(ERROR_CFLAGS) $(CFLAGS) -dM > -E -xc - </dev/null 2>/dev/null | grep -c 'LOCK_FREE.*[12]'),0) > USE_LIBATOMIC = implicit > endif > endif It would impose libatomic for everyone, and not everyone has it. For example this would break clang on freebsd from what I'm seeing. That's not logic, there must be another reason. Willy
