5 files changed, 44 insertions, 14 deletions
diff --git a/libc/sysdeps/linux/arm/bits/profil-counter.h b/libc/sysdeps/linux/arm/bits/profil-counter.h
index 5d8be9dba..7639883f1 100644
--- a/libc/sysdeps/linux/arm/bits/profil-counter.h
+++ b/libc/sysdeps/linux/arm/bits/profil-counter.h
@@ -1,5 +1,5 @@
 /* Low-level statistical profiling support function.  Linux/ARM version.
-   Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+   Copyright (C) 1996, 1997, 1998, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -29,4 +29,9 @@ profil_counter (int signo, int _a2, int _a3, int _a4, union k_sigcontext sc)
   else
     pc = (void *) sc.v21.arm_pc;
   profil_count (pc);
+
+  /* This is a hack to prevent the compiler from implementing the
+     above function call as a sibcall.  The sibcall would overwrite
+     the signal context.  */
+  asm volatile ("");
 }
diff --git a/libc/sysdeps/linux/arm/bits/sigcontextinfo.h b/libc/sysdeps/linux/arm/bits/sigcontextinfo.h
index aebc3cfd5..30c2e3a6c 100644
--- a/libc/sysdeps/linux/arm/bits/sigcontextinfo.h
+++ b/libc/sysdeps/linux/arm/bits/sigcontextinfo.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1999 Free Software Foundation, Inc.
+/* Copyright (C) 1999, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Philip Blundell <philb@gnu.org>, 1999.
 
@@ -18,10 +18,22 @@
    02111-1307 USA.  */
 
 #include <bits/armsigctx.h>
+#include "kernel-features.h"
 
 #define SIGCONTEXT int _a2, int _a3, int _a4, union k_sigcontext
 #define SIGCONTEXT_EXTRA_ARGS _a2, _a3, _a4,
 
+/* The sigcontext structure changed between 2.0 and 2.1 kernels.  On any
+   modern system we should be able to assume that the "new" format will be
+   in use.  */
+#if __LINUX_KERNEL_VERSION > 131328
+
+#define GET_PC(ctx)	((void *) ctx.v21.arm_pc)
+#define GET_FRAME(ctx)	ADVANCE_STACK_FRAME ((void *) ctx.v21.arm_fp)
+#define GET_STACK(ctx)	((void *) ctx.v21.arm_sp)
+
+#else
+
 #define GET_PC(ctx)	((void *)((ctx.v20.magic == SIGCONTEXT_2_0_MAGIC) ? \
 			 ctx.v20.reg.ARM_pc : ctx.v21.arm_pc))
 #define GET_FRAME(ctx)	\
@@ -29,7 +41,11 @@
 			 ctx.v20.reg.ARM_fp : ctx.v21.arm_fp))
 #define GET_STACK(ctx)	((void *)((ctx.v20.magic == SIGCONTEXT_2_0_MAGIC) ? \
 			 ctx.v20.reg.ARM_sp : ctx.v21.arm_sp))
+
+#endif
+
 #define ADVANCE_STACK_FRAME(frm)	\
 			((struct layout *)frm - 1)
+
 #define CALL_SIGHANDLER(handler, signo, ctx) \
   (handler)((signo), SIGCONTEXT_EXTRA_ARGS (ctx))
diff --git a/libc/sysdeps/linux/i386/bits/profil-counter.h b/libc/sysdeps/linux/i386/bits/profil-counter.h
index 80933a36f..69045b55b 100644
--- a/libc/sysdeps/linux/i386/bits/profil-counter.h
+++ b/libc/sysdeps/linux/i386/bits/profil-counter.h
@@ -1,5 +1,5 @@
 /* Low-level statistical profiling support function.  Linux/i386 version.
-   Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+   Copyright (C) 1996, 1997, 1998, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -21,7 +21,12 @@
 #include <bits/sigcontextinfo.h>
 
 static void
-profil_counter (int signo, SIGCONTEXT scp)
+profil_counter (int signo, const SIGCONTEXT scp)
 {
   profil_count ((void *) GET_PC (scp));
+
+  /* This is a hack to prevent the compiler from implementing the
+     above function call as a sibcall.  The sibcall would overwrite
+     the signal context.  */
+  asm volatile ("");
 }
diff --git a/libc/sysdeps/linux/powerpc/bits/profil-counter.h b/libc/sysdeps/linux/powerpc/bits/profil-counter.h
index 6ce7eab01..69045b55b 100644
--- a/libc/sysdeps/linux/powerpc/bits/profil-counter.h
+++ b/libc/sysdeps/linux/powerpc/bits/profil-counter.h
@@ -1,5 +1,5 @@
-/* Low-level statistical profiling support function.  Linux/ipowerpc version.
-   Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+/* Low-level statistical profiling support function.  Linux/i386 version.
+   Copyright (C) 1996, 1997, 1998, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -21,8 +21,12 @@
 #include <bits/sigcontextinfo.h>
 
 static void
-profil_counter (int signo, SIGCONTEXT scp)
+profil_counter (int signo, const SIGCONTEXT scp)
 {
   profil_count ((void *) GET_PC (scp));
-}
 
+  /* This is a hack to prevent the compiler from implementing the
+     above function call as a sibcall.  The sibcall would overwrite
+     the signal context.  */
+  asm volatile ("");
+}
diff --git a/libc/sysdeps/linux/sh/bits/profil-counter.h b/libc/sysdeps/linux/sh/bits/profil-counter.h
index 44561b2a6..ae1b97828 100644
--- a/libc/sysdeps/linux/sh/bits/profil-counter.h
+++ b/libc/sysdeps/linux/sh/bits/profil-counter.h
@@ -1,5 +1,5 @@
 /* Low-level statistical profiling support function.  Linux/SH version.
-   Copyright (C) 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1996, 1997, 1998, 2000, 2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -23,11 +23,11 @@ static void
 profil_counter (int signo, int _a2, int _a3, int _a4, struct sigcontext sc)
 {
   void *pc;
-  (void) signo;
-  (void)_a2;
-  (void)_a3;
-  (void)_a4;
-  
   pc = (void *) sc.sc_pc;
   profil_count (pc);
+
+  /* This is a hack to prevent the compiler from implementing the
+     above function call as a sibcall.  The sibcall would overwrite
+     the signal context.  */
+  asm volatile ("");
 }