qa: add test that crash with -O2

qa/gnu/gcc/hello.c

@@ -0,0 +1,47 @@
+/*
+ * This file is part of Jehanne.
+ *
+ * Copyright (C) 2015 Giacomo Tesio <giacomo@tesio.it>
+ *
+ * Jehanne is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * Jehanne is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Jehanne.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <u.h>
+#include <lib9.h>
+
+#define Mb (1024*1024)
+
+/*
+ */
+void
+main(int argc, char**argv)
+{
+	char *v;
+	int i, j;
+
+	j = 5;
+/*	
+	for(j = 5; i > 0; j--){
+		v = malloc(j*Mb);
+		for(i = 0; i < j*Mb; i += 512)
+			v[i] = 'a';
+		free(v);
+	}
+*/
+		v = malloc(j*Mb);
+		for(i = 0; i < j*Mb; i += 512)
+			v[i] = 'a';
+		free(v);
+	
+	print("PASS\n");
+	exits("PASS");
+}