From 1b64a5f5f0cece3cf0009410ddb13b5dd6f899e1 Mon Sep 17 00:00:00 2001 From: Vexu Date: Wed, 1 Jan 2020 15:24:46 +0200 Subject: [PATCH] fix segfault in bit shift safety check --- src/ir.cpp | 10 +++++++--- test/stage1/behavior/bit_shifting.zig | 4 ++++ 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/src/ir.cpp b/src/ir.cpp index 7cc1829341..ddfed8229b 100644 --- a/src/ir.cpp +++ b/src/ir.cpp @@ -15621,11 +15621,15 @@ static IrInstruction *ir_analyze_bit_shift(IrAnalyze *ira, IrInstructionBinOp *b op1->value->type->data.integral.bit_count - 1); if (bin_op_instruction->op_id == IrBinOpBitShiftLeftLossy && op2->value->type->id == ZigTypeIdComptimeInt) { - if (!bigint_fits_in_bits(&op2->value->data.x_bigint, + + ZigValue *op2_val = ir_resolve_const(ira, op2, UndefBad); + if (op2_val == nullptr) + return ira->codegen->invalid_instruction; + if (!bigint_fits_in_bits(&op2_val->data.x_bigint, shift_amt_type->data.integral.bit_count, - op2->value->data.x_bigint.is_negative)) { + op2_val->data.x_bigint.is_negative)) { Buf *val_buf = buf_alloc(); - bigint_append_buf(val_buf, &op2->value->data.x_bigint, 10); + bigint_append_buf(val_buf, &op2_val->data.x_bigint, 10); ErrorMsg* msg = ir_add_error(ira, &bin_op_instruction->base, buf_sprintf("RHS of shift is too large for LHS type")); diff --git a/test/stage1/behavior/bit_shifting.zig b/test/stage1/behavior/bit_shifting.zig index 3c5d4aa64c..84d5f8f60e 100644 --- a/test/stage1/behavior/bit_shifting.zig +++ b/test/stage1/behavior/bit_shifting.zig @@ -96,3 +96,7 @@ test "comptime shr of BigInt" { std.debug.assert(n1 >> 64 == 0); } } + +test "comptime shift safety check" { + const x = @as(usize, 42) << @sizeOf(usize); +}