[PATCH] i386: fix prevent_tail_call

[Roland McGrath]

We fixed this bug before, but it didn't take.  It may have been the case
that the problem was first noticed to occur in a CONFIG_REGPARM compile.
But it's not regparm functions that need not to make tail calls, it's
asmlinkage functions called with a user pt_regs frame on the stack
supplying their arguments.  prevent_tail_call probably doesn't do anything
at all in regparm functions (your argument registers are going to be
clobbered, period).  It was a braino to conditionalize that definition in
the first place.

Signed-off-by: Roland McGrath <roland@xxxxxxxxxx>

---
commit 20da6762d8c1921800686ce31b1563e3ac24880d
tree cffaf6d5044bb44f13bb540d750f1e44562901e4
parent 3b54f47d661b933498f0709e5ce215d0f285e928
author Roland McGrath <roland@xxxxxxxxxx> Thu, 26 May 2005 15:19:26 -0700
committer Roland McGrath <roland@xxxxxxxxxx> Thu, 26 May 2005 15:19:26 -0700

 asm-i386/linkage.h |    4 +---
 1 files changed, 1 insertion(+), 3 deletions(-)

Index: include/asm-i386/linkage.h
===================================================================
--- a2dc8eec0e30ffa0f39d2f835e018ee86387ff61/include/asm-i386/linkage.h  (mode:100644)
+++ cffaf6d5044bb44f13bb540d750f1e44562901e4/include/asm-i386/linkage.h  (mode:100644)
@@ -5,9 +5,7 @@
 #define FASTCALL(x)	x __attribute__((regparm(3)))
 #define fastcall	__attribute__((regparm(3)))
 
-#ifdef CONFIG_REGPARM
-# define prevent_tail_call(ret) __asm__ ("" : "=r" (ret) : "0" (ret))
-#endif
+#define prevent_tail_call(ret) __asm__ ("" : "=r" (ret) : "0" (ret))
 
 #ifdef CONFIG_X86_ALIGNMENT_16
 #define __ALIGN .align 16,0x90
-
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