From 1c232ca6e828a382b645bfaa4f964f581a1486fb Mon Sep 17 00:00:00 2001
From: Vedant Madane <6527493+VedantMadane@users.noreply.github.com>
Date: Tue, 25 Aug 2026 01:55:59 +0530
Subject: [PATCH] fix: Guard zero compressed size in CLI trace ratio

- guard ratio against zero compressedSize

Fixes #4368

Signed-off-by: Vedant Madane <6527493+VedantMadane@users.noreply.github.com>
---
 programs/zstdcli_trace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/programs/zstdcli_trace.c b/programs/zstdcli_trace.c
index f73071a5cf4..132ac25a60c 100644
--- a/programs/zstdcli_trace.c
+++ b/programs/zstdcli_trace.c
@@ -82,7 +82,7 @@ static void TRACE_log(char const* method, PTime duration, ZSTD_Trace const* trac
     int level = 0;
     int workers = 0;
     double const durationAsDouble = duration ? (double)duration : .1;
-    double const ratio = (double)trace->uncompressedSize / (double)trace->compressedSize;
+    double const ratio = trace->compressedSize ? ((double)trace->uncompressedSize / (double)trace->compressedSize) : 0.;
     double const speed = ((double)trace->uncompressedSize * 1000) / durationAsDouble;
     if (trace->params) {
         ZSTD_CCtxParams_getParameter(trace->params, ZSTD_c_compressionLevel, &level);