gen-num-limits.cc: Use sigsetjmp and siglongjmp if available.

* src/gen-num-limits.cc: Use sigsetjmp and siglongjmp if available.
* mknumeric_limits: Compile it with -DHAVE_CONFIG_H.
* configure.in: Test for sigsetjmp.
* configure, config.h.in: Rebuilt.

From-SVN: r39586

libstdc++-v3/ChangeLog

+2001-02-11  Alexandre Oliva  <aoliva@redhat.com>
+
+	* src/gen-num-limits.cc: Use sigsetjmp and siglongjmp if available.
+	* mknumeric_limits: Compile it with -DHAVE_CONFIG_H.
+	* configure.in: Test for sigsetjmp.
+	* configure, config.h.in: Rebuilt.
+
 2001-02-11  Gabriel Dos Reis  <gdr@codesourcery.com>
 
 	* src/valarray-inst.cc (gslice::_Indexer::_Indexer): Don't flip 

libstdc++-v3/config.h.in

@@ -546,6 +546,9 @@
 /* Version number of package */
 #undef VERSION
 
+/* Define if sigsetjmp is available.   */
+#undef HAVE_SIGSETJMP
+
 //
 // Systems that have certain non-standard functions prefixed with an
 // underscore, we'll handle those here. Must come after config.h.in.

libstdc++-v3/configure.in

@@ -217,6 +217,11 @@ else
   GLIBCPP_CHECK_WCHAR_T_SUPPORT
   GLIBCPP_CHECK_STDLIB_SUPPORT
 
+  AC_TRY_COMPILE([
+#include <setjmp.h>
+], [sigjmp_buf env; while (! sigsetjmp (env, 1)) siglongjmp (env, 1);],
+[AC_DEFINE(HAVE_SIGSETJMP, 1, [Define if sigsetjmp is available.  ])])
+
   AC_FUNC_MMAP
 fi
 

libstdc++-v3/mknumeric_limits

@@ -178,18 +178,17 @@ namespace std {
 
 EOF
 
-echo "$CXX $CPPFLAGS -I$BUILD_DIR/include \
+echo "$CXX -I. $CPPFLAGS -I$BUILD_DIR/include -DHAVE_CONFIG_H \
     -o "$BUILD_DIR/src/gen-num-limits" "$SRC_DIR/src/gen-num-limits.cc" \
      $LDFLAGS"
 
-$CXX $CPPFLAGS -I$BUILD_DIR/include \
+{ $CXX -I. $CPPFLAGS -I$BUILD_DIR/include -DHAVE_CONFIG_H \
     -o "$BUILD_DIR/src/gen-num-limits" "$SRC_DIR/src/gen-num-limits.cc" \
      $LDFLAGS
-
-if [ ! -f "$BUILD_DIR/src/gen-num-limits" ]; then
+} || {
   echo "gen-num-limits failed to build, exiting."
   exit 1
-fi
+}
 
 "$BUILD_DIR/src/gen-num-limits" >> $OUT_H-t
 

libstdc++-v3/src/gen-num-limits.cc

@@ -35,6 +35,10 @@
 
 #include <bits/c++config.h>
 
+#if HAVE_CONFIG_H
+# include <config.h>
+#endif
+
 //
 // Force Linux <limits.h> to define the *LONG_LONG*
 //
@@ -57,6 +61,18 @@
 #include <wchar.h>
 #endif
 
+// mknumeric_limits will first try to compile this file with
+// HAVE_SIGSETJMP.  If it fails, then it will try without it.  Some
+// systems, such as GNU/Linux/sparc, would remain with the signal
+// blocked if the signal handler uses longjmp instead of siglongjmp.
+// We assume here setjmp/longjmp will preserve the sigblock mask if
+// sigsetjmp is not present.
+
+#if ! HAVE_SIGSETJMP 
+# define sigjmp_buf jmp_buf 
+# define sigsetjmp(buf, save) setjmp (buf) 
+# define siglongjmp(env, ret) longjmp (env, ret) 
+#endif 
 
 const char tab[] = "    ";
 const char tab2[] = "        ";
@@ -90,7 +106,7 @@ const int integer_base_rep = 2;
 // occur for int, unsigned, long, unsigned long. Furthermore
 // overflow cannot happen for unsigned integer types.
 
-jmp_buf env;
+sigjmp_buf env;
 
 /* The prototype of signal() may vary.  Accomodate variations such as
    void(*)(int) and void(*)(...).  */
@@ -112,13 +128,13 @@ void signal_handler(int sig)
   sigemptyset (&x);
   sigprocmask(SIG_SETMASK, &x, NULL);
 #endif /* __CYGWIN__ */
-  longjmp(env, sig); 
+  siglongjmp(env, sig); 
 }
 
 template<typename Operation>
 bool trapping(const Operation& op)
 {
-    if (setjmp(env) == 0) op();
+    if (sigsetjmp(env, 1) == 0) op();
     else return true;
     return false;
 }