[PATCH] RISC-V: Suppress riscv-selftests.cc warning.

[juzhe . zhong]

From: Ju-Zhe Zhong <juzhe.zh...@rivai.ai>

This patch is a fix patch for:
https://gcc.gnu.org/pipermail/gcc-patches/2022-September/601643.html

Suppress the warning as follows:

../../../riscv-gcc/gcc/poly-int.h: In function
‘poly_int64 eval_value(rtx, std::map<unsigned int, rtx_def*>&)’:
../../../riscv-gcc/gcc/poly-int.h:845:48: warning:
‘*((void*)& op2_val +8)’ may be used uninitialized
in this function [-Wmaybe-uninitialized]
     POLY_SET_COEFF (C, r, i, NCa (a.coeffs[i]) + b.coeffs[i]);
                                                ^
../../../riscv-gcc/gcc/config/riscv/riscv-selftests.cc:74:23:
note: ‘*((void*)& op2_val +8)’ was declared here
   poly_int64 op1_val, op2_val;

gcc/ChangeLog:

        * config/riscv/riscv-selftests.cc (eval_value): Add initial value.

---
 gcc/config/riscv/riscv-selftests.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gcc/config/riscv/riscv-selftests.cc 
b/gcc/config/riscv/riscv-selftests.cc
index 167cd47c880..490b6ed6b8e 100644
--- a/gcc/config/riscv/riscv-selftests.cc
+++ b/gcc/config/riscv/riscv-selftests.cc
@@ -71,7 +71,8 @@ eval_value (rtx x, std::map<unsigned, rtx> &regno_to_rtx)
   unsigned regno = REGNO (x);
   expr = regno_to_rtx[regno];
 
-  poly_int64 op1_val, op2_val;
+  poly_int64 op1_val = 0;
+  poly_int64 op2_val = 0;
   if (UNARY_P (expr))
     {
       op1_val = eval_value (XEXP (expr, 0), regno_to_rtx);
-- 
2.36.1