setjmp: Use BSD sematic as default for setjmp

POSIX relaxed the relation of setjmp/longjmp and the signal mask
save/restore, meaning that setjmp does not require to be routed to
_setjmp to be standard compliant.

This is done to avoid breakage of SIGABRT handlers, since to fully
make abort AS-safe, it is required to remove the recurisve lock
used to unblock SIGABRT prior raised the signal.

Also, it allows caller to actually use setjmp, since from
7011c2622fe3e10a29dbe74f06aaebd07710127d the symbol is unconditionally
routed to _setjmp.

Checked on x86_64-linux-gnu.

diff --git a/manual/setjmp.texi b/manual/setjmp.texi
index 7092a0dde2db70100f0c157e953951076ae4bf43..f2d82a2f33e4c0a765cc12fc8c569c614c207b49 100644 (file)
--- a/manual/setjmp.texi
+++ b/manual/setjmp.texi
@@ -189,16 +189,10 @@ them @code{volatile}.
 @section Non-Local Exits and Signals
 
 In BSD Unix systems, @code{setjmp} and @code{longjmp} also save and
-restore the set of blocked signals; see @ref{Blocking Signals}.  However,
-the POSIX.1 standard requires @code{setjmp} and @code{longjmp} not to
-change the set of blocked signals, and provides an additional pair of
-functions (@code{sigsetjmp} and @code{siglongjmp}) to get the BSD
-behavior.
-
-The behavior of @code{setjmp} and @code{longjmp} in @theglibc{} is
-controlled by feature test macros; see @ref{Feature Test Macros}.  The
-default in @theglibc{} is the POSIX.1 behavior rather than the BSD
-behavior.
+restore the set of blocked signals; see @ref{Blocking Signals}, while
+on @w{System V} they will not.  POSIX does not specify the relation of
+@code{setjmp} and @code{longjmp} to signal mask.  The default in
+@theglibc{} is the BSD behavior.
 
 The facilities in this section are declared in the header file
 @file{setjmp.h}.

diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c
index 1d3665d5edb684e3de0e070763914a90b47545c7..527cb9017d8b2d4b763c29d4e5a2ee5e8ba11abf 100644 (file)
--- a/nptl/pthread_create.c
+++ b/nptl/pthread_create.c
@@ -402,7 +402,8 @@ start_thread (void *arg)
      the saved signal mask), so that is a false positive.  */
   DIAG_IGNORE_NEEDS_COMMENT (11, "-Wstringop-overflow=");
 #endif
-  not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf);
+  not_first_call = __sigsetjmp (
+    (struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf, 0);
   DIAG_POP_NEEDS_COMMENT;
 
   /* No previous handlers.  NB: This must be done after setjmp since the

diff --git a/setjmp/setjmp.h b/setjmp/setjmp.h
index 1309c6210d17ae31ea89cd8bc9e92258a3f405c9..98efa3e863eba39390e008e2fedbf37dc5903e31 100644 (file)
--- a/setjmp/setjmp.h
+++ b/setjmp/setjmp.h
@@ -44,11 +44,6 @@ extern int __sigsetjmp (struct __jmp_buf_tag __env[1], int __savemask) __THROWNL
    Return 0.  */
 extern int _setjmp (struct __jmp_buf_tag __env[1]) __THROWNL;
 
-/* Do not save the signal mask.  This is equivalent to the `_setjmp'
-   BSD function.  */
-#define setjmp(env)    _setjmp (env)
-
-
 /* Jump to the environment saved in ENV, making the
    `setjmp' call there return VAL, or 1 if VAL is 0.  */
 extern void longjmp (struct __jmp_buf_tag __env[1], int __val)

diff --git a/sysdeps/nptl/libc_start_call_main.h b/sysdeps/nptl/libc_start_call_main.h
index 26ac8dd53ba20c40398ab54b66b74d7c82c80bfc..c41ca6843b5bfdda7f94382de606d1303d29a8e2 100644 (file)
--- a/sysdeps/nptl/libc_start_call_main.h
+++ b/sysdeps/nptl/libc_start_call_main.h
@@ -41,7 +41,8 @@ __libc_start_call_main (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
      the saved signal mask), so that is a false positive.  */
   DIAG_IGNORE_NEEDS_COMMENT (11, "-Wstringop-overflow=");
 #endif
-  not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf);
+  not_first_call = __sigsetjmp (
+     (struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf, 0);
   DIAG_POP_NEEDS_COMMENT;
   if (__glibc_likely (! not_first_call))
     {