1 files changed, 1 insertions, 1 deletions
diff --git a/cop.h b/cop.h
index c11687d3dc..83f1f04bd2 100644
--- a/cop.h
+++ b/cop.h
@@ -330,7 +330,7 @@ struct block_sub {
 	    POP_SAVEARRAY();						\
 	    /* abandon @_ if it got reified */				\
 	    if (AvREAL(cx->blk_sub.argarray)) {				\
-		SSize_t fill = AvFILLp(cx->blk_sub.argarray);		\
+		const SSize_t fill = AvFILLp(cx->blk_sub.argarray);	\
 		SvREFCNT_dec(cx->blk_sub.argarray);			\
 		cx->blk_sub.argarray = newAV();				\
 		av_extend(cx->blk_sub.argarray, fill);			\