backtrace: Use generic code to find the bottom of the stack.

This fixes an ugly GCC warning without using inline asm.

diff --git a/AUTHORS b/AUTHORS
index c396dcf..6037ffa 100644 (file)
--- a/AUTHORS
+++ b/AUTHORS
@@ -24,6 +24,7 @@ Tetsuo NAKAGAWA         nakagawa@mxc.nes.nec.co.jp
 Thomas Lacroix          thomas.lacroix@citrix.com
 Todd Deshane            deshantm@gmail.com
 Tom Everman             teverman@google.com
+Tsvi Slonim             tsvi@toroki.com
 Wei Yongjun             yjwei@cn.fujitsu.com
 Yu Zhiguo               yuzg@cn.fujitsu.com
 

diff --git a/lib/backtrace.c b/lib/backtrace.c
index 131bdf4..d2d1e40 100644 (file)
--- a/lib/backtrace.c
+++ b/lib/backtrace.c
@@ -69,20 +69,8 @@ stack_high(void)
 static uintptr_t
 stack_low(void)
 {
-#ifdef __i386__
-    uintptr_t low;
-    asm("movl %%esp,%0" : "=g" (low));
+    uintptr_t low = (uintptr_t) &low;
     return low;
-#elif __x86_64__
-    uintptr_t low;
-    asm("movq %%rsp,%0" : "=g" (low));
-    return low;
-#else
-    /* This causes a warning in GCC that cannot be disabled, so use it only on
-     * non-x86. */
-    int dummy;
-    return (uintptr_t) &dummy;
-#endif
 }
 
 static bool