[PATCH] compile-i386: do not generate an infinite loop

[Kamil Dudka <kdudka@redhat.com>]

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Hello,

I've probably encountered a bug within compile-i386.c. It generates
an infinite loop for 'while' statement. My testing example and proposed
patch are enclosed.

Kamil

[-- Attachment #2: list.c --]
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#include <stdlib.h>

typedef void *TItem;

void dispose_list(TItem *list) {
    while (list) {
        TItem *item = list;
        list = (TItem *) *list;
        free(item);
    }
}

[-- Attachment #3: 0001-compile-i386-do-not-generate-an-infinite-loop.patch --]
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From 60c47d120b577092f0d8fe9001ca6753706dcdbc Mon Sep 17 00:00:00 2001
From: Kamil Dudka <kdudka@redhat.com>
Date: Sat, 18 Jul 2009 23:24:38 +0200
Subject: [PATCH] compile-i386: do not generate an infinite loop

---
 compile-i386.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/compile-i386.c b/compile-i386.c
index 37ea52e..abe9313 100644
--- a/compile-i386.c
+++ b/compile-i386.c
@@ -1913,6 +1913,10 @@ static void emit_loop(struct statement *stmt)
 
 	x86_symbol_decl(stmt->iterator_syms);
 	x86_statement(pre_statement);
+	if (!post_condition || post_condition->type != EXPR_VALUE || post_condition->value) {
+		loop_top = new_label();
+		emit_label(loop_top, "loop top");
+	}
 	if (pre_condition) {
 		if (pre_condition->type == EXPR_VALUE) {
 			if (!pre_condition->value) {
@@ -1936,10 +1940,6 @@ static void emit_loop(struct statement *stmt)
 			insn("jz", lbv, NULL, NULL);
 		}
 	}
-	if (!post_condition || post_condition->type != EXPR_VALUE || post_condition->value) {
-		loop_top = new_label();
-		emit_label(loop_top, "loop top");
-	}
 	x86_statement(statement);
 	if (stmt->iterator_continue->used)
 		emit_label(loop_continue, "'continue' iterator");
-- 
1.6.3.3