From ff202817dc2b0b3b42992fa7f1ce503f081068fe Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 28 Feb 2024 12:06:41 +0100 Subject: [PATCH] tcg/optimize: fix uninitialized variable MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The variables uext_opc and sext_opc are used without initialization if TCG_TARGET_extract_i{32,64}_valid returns false. The result, depending on the compiler, might be the generation of extract and sextract opcodes with invalid offset and count, or just random data in the TCG opcode stream. Fixes: ceb9ee06b71 ("tcg/optimize: Handle TCG_COND_TST{EQ,NE}", 2024-02-03) Cc: Richard Henderson Signed-off-by: Paolo Bonzini Reviewed-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-Id: <20240228110641.287205-1-pbonzini@redhat.com> Signed-off-by: Richard Henderson --- tcg/optimize.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tcg/optimize.c b/tcg/optimize.c index 79e701652b..752cc5c56b 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -2102,7 +2102,8 @@ static bool fold_remainder(OptContext *ctx, TCGOp *op) static void fold_setcond_tst_pow2(OptContext *ctx, TCGOp *op, bool neg) { - TCGOpcode and_opc, sub_opc, xor_opc, neg_opc, shr_opc, uext_opc, sext_opc; + TCGOpcode and_opc, sub_opc, xor_opc, neg_opc, shr_opc; + TCGOpcode uext_opc = 0, sext_opc = 0; TCGCond cond = op->args[3]; TCGArg ret, src1, src2; TCGOp *op2;