Building with `"DEBUG=-DDEBUG_STRICT=1 -DDEBUG_USE_ABORT=1"` previously emitted the warning:
In file included from include/haproxy/api.h:35:0,
from src/mux_pt.c:13:
include/haproxy/buf.h: In function ‘br_init’:
include/haproxy/bug.h:42:90: warning: implicit declaration of function ‘abort’ [-Wimplicit-function-declaration]
#define ABORT_NOW() do { extern void ha_backtrace_to_stderr(); ha_backtrace_to_stderr(); abort(); } while (0)
^
include/haproxy/bug.h:56:21: note: in expansion of macro ‘ABORT_NOW’
#define CRASH_NOW() ABORT_NOW()
^
include/haproxy/bug.h:68:4: note: in expansion of macro ‘CRASH_NOW’
CRASH_NOW(); \
^
include/haproxy/bug.h:62:35: note: in expansion of macro ‘__BUG_ON’
#define _BUG_ON(cond, file, line) __BUG_ON(cond, file, line)
^
include/haproxy/bug.h:61:22: note: in expansion of macro ‘_BUG_ON’
#define BUG_ON(cond) _BUG_ON(cond, __FILE__, __LINE__)
^
include/haproxy/buf.h:875:2: note: in expansion of macro ‘BUG_ON’
BUG_ON(size < 2);
^
This patch fixes that issue. The `DEBUG_USE_ABORT` option exists for use with
static analysis tools. No backport needed.
For whatever reason, glibc decided that the __attribute__ keyword is
the exclusive property of gcc, and redefines it to an empty macro on
other compilers. Some non-gcc compilers also support it (possibly
partially), tinycc is one of them. By doing this, glibc silently
broke all constructors, resulting in code that arrives in main() with
uninitialized variables.
The solution we use here consists in undefining the macro on non-gcc
compilers, and redefining it to itself in order to cause a conflict in
the event the redefinition would happen afterwards. This visibly solved
the problem.
Some checks on __GNUC__ imply that if it's undefined it will match a
low value but that's not always what we want, like for example in the
VAR_ARRAY definition which is not needed on tcc. Let's always be explicit
on these tests.
This macro is provided by clang but gcc lacks it. Not having it makes
it painful to test features on both compilers. Better define it to zero
when not available so that __has_feature(foo) never errors.
Since these are used as type attributes or conditional clauses, they
are used about everywhere and should not require a dependency on
thread.h. Moving them to compiler.h along with other similar statements
like ALIGN() etc looks more logical; this way they become part of the
base API. This allowed to remove thread-t.h from ~12 files, one was
found to only require thread-t and not thread and dict.c was found to
require thread.h.
Sometimes we need to align a struct member or a struct's size only when
threads are enabled. This is the case on fdtab for example. Instead of
using ugly ifdefs in the code itself, let's have a THREAD_ALIGNED() macro
performing the alignment only when threads are enabled. For now this was
only applied to fd-t.h as it was the only place found.
