https://gcc.gnu.org/g:621e567cae24d12f4eb34d0e37889bfb8ec0d036
commit 621e567cae24d12f4eb34d0e37889bfb8ec0d036 Author: Jeff Law <[email protected]> Date: Mon May 19 12:00:56 2025 -0600 [RISC-V] Fix false positive from Wuninitialized As Mark and I independently tripped, there's a Wuninitialized issue in the RISC-V backend. While *I* know the value would always be properly initialized, it'd be somewhat painful to either eliminate the infeasible paths or do deep enough analysis to suppress the false positive. So this initializes OUTPUT and verifies it's got a reasonable value before using it for the final copy into operands[0]. Bootstrapped on the BPI (regression testing still has ~12hrs to go). gcc/ * config/riscv/riscv.cc (synthesize_ior_xor): Initialize OUTPUT and verify it's non-null before emitting the final copy insn. (cherry picked from commit cbc258cd318756db8b5f0e4055dd8f1c1d618d22) Diff: --- gcc/config/riscv/riscv.cc | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc index 3f5f0e727665..a7c20eec4fc8 100644 --- a/gcc/config/riscv/riscv.cc +++ b/gcc/config/riscv/riscv.cc @@ -14446,7 +14446,7 @@ synthesize_ior_xor (rtx_code code, rtx operands[3]) /* Synthesis is better than loading the constant. */ ival = INTVAL (operands[2]); rtx input = operands[1]; - rtx output; + rtx output = NULL_RTX; /* Emit the [x]ori insn that sets the low 11 bits into the proper state. */ @@ -14475,6 +14475,8 @@ synthesize_ior_xor (rtx_code code, rtx operands[3]) input = output; ival &= ~tmpval; } + + gcc_assert (output); emit_move_insn (operands[0], output); return true; }
