diff --git a/lib/compress/zstd_opt.h b/lib/compress/zstd_opt.h
index 703b568e2..8b15bf6ad 100644
--- a/lib/compress/zstd_opt.h
+++ b/lib/compress/zstd_opt.h
@@ -574,7 +574,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
            best_mlen = minMatch;
            {   U32 i;
                for (i=0; i<ZSTD_REP_NUM; i++) {
-                   if ((rep[i]<(U32)(inr-prefixStart))
+                   if ((opt[cur].rep[i]<(U32)(inr-prefixStart))
                        && (MEM_readMINMATCH(inr, minMatch) == MEM_readMINMATCH(inr - opt[cur].rep[i], minMatch))) {  /* check rep */
                        mlen = (U32)ZSTD_count(inr+minMatch, inr+minMatch - opt[cur].rep[i], iend) + minMatch;
                        ZSTD_LOG_PARSER("%d: Found REP %d/%d mlen=%d off=%d rep=%d opt[%d].off=%d\n", (int)(inr-base), i, ZSTD_REP_NUM, mlen, i, opt[cur].rep[i], cur, opt[cur].off);