[gcc(refs/vendors/riscv/heads/gcc-15-with-riscv-opts)] [RISC-V] Fix trivial bootstrap failure on RISC-V

[Jeff Law]

https://gcc.gnu.org/g:a3b46ff2411eb0eab0db52ad90d9ae63931f599b

commit a3b46ff2411eb0eab0db52ad90d9ae63931f599b
Author: Jeff Law <jlaw@ventanamicro.com>
Date:   Wed Nov 19 06:34:33 2025 -0700

    [RISC-V] Fix trivial bootstrap failure on RISC-V
    
    Trivial bootstrap fix for the RISC-V port where a recent change introduced a
    signed vs unsigned warning.
    
    gcc/
            * config/riscv/riscv-string.cc (riscv_expand_block_move_scalar):
            Fix signed vs unsigned warning.
    
    (cherry picked from commit a3e97daf1f7452d060d2e5e4eb2fea7717343f18)

Diff:
---
 gcc/config/riscv/riscv-string.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/config/riscv/riscv-string.cc b/gcc/config/riscv/riscv-string.cc
index 2d662b4ce495..c5710e4c8962 100644
--- a/gcc/config/riscv/riscv-string.cc
+++ b/gcc/config/riscv/riscv-string.cc
@@ -924,7 +924,7 @@ riscv_expand_block_move_scalar (rtx dest, rtx src, rtx length)
   unsigned HOST_WIDE_INT factor, align;
 
   if (riscv_memcpy_size_threshold >= 0
-      && hwi_length > riscv_memcpy_size_threshold)
+      && hwi_length > (unsigned HOST_WIDE_INT) riscv_memcpy_size_threshold)
     return false;
 
   if (riscv_slow_unaligned_access_p)