gcconfig.h (sparc-linux): Use LINUX_STACKBOTTOM.

2005-04-17  David S. Miller  <davem@davemloft.net>

	* include/private/gcconfig.h (sparc-linux): Use LINUX_STACKBOTTOM.
	* os_dep.c (GC_linux_stack_base): Check for bug present in some
	Sparc glibc variants where __libc_stack_end is erroneously set
	to "1".  Fallback to procfs code in that case.

From-SVN: r98303

boehm-gc/ChangeLog

+2005-04-17  David S. Miller  <davem@davemloft.net>
+
+	* include/private/gcconfig.h (sparc-linux): Use LINUX_STACKBOTTOM.
+	* os_dep.c (GC_linux_stack_base): Check for bug present in some
+	Sparc glibc variants where __libc_stack_end is erroneously set
+	to "1".  Fallback to procfs code in that case.
+
 2005-04-12  Mike Stump  <mrs@apple.com>
 
 	* configure: Regenerate.

boehm-gc/include/private/gcconfig.h

@@ -924,12 +924,10 @@
       extern ptr_t GC_SysVGetDataStart();
 #     ifdef __arch64__
 #	define DATASTART GC_SysVGetDataStart(0x100000, _etext)
-	/* libc_stack_end is not set reliably for sparc64 */
-#       define STACKBOTTOM ((ptr_t) 0x80000000000ULL)
 #     else
 #       define DATASTART GC_SysVGetDataStart(0x10000, _etext)
-#	define LINUX_STACKBOTTOM
 #     endif
+#     define LINUX_STACKBOTTOM
 #   endif
 #   ifdef OPENBSD
 #     define OS_TYPE "OPENBSD"

boehm-gc/os_dep.c

@@ -945,8 +945,17 @@ ptr_t GC_get_stack_base()
 	  } /* Otherwise it's not safe to add 16 bytes and we fall	*/
 	    /* back to using /proc.					*/
 #	else 
+#	ifdef SPARC
+	  /* Older versions of glibc for 64-bit Sparc do not set
+	   * this variable correctly, it gets set to either zero
+	   * or one.
+	   */
+	  if (__libc_stack_end != (ptr_t) (unsigned long)0x1)
+	    return __libc_stack_end;
+#	else
 	  return __libc_stack_end;
 #	endif
+#	endif
       }
     f = open("/proc/self/stat", O_RDONLY);
     if (f < 0 || STAT_READ(f, stat_buf, STAT_BUF_SIZE) < 2 * STAT_SKIP) {