detect/port: add BUG_ON on impossible condition

to assist Coverity in assessing the state of x correctly.

diff --git a/src/detect-engine-port.c b/src/detect-engine-port.c
index 7d8b15a22c3d55ce1f74d3df6a19884bc257e927..07b0ebc13a3d1bbe41e065c52e2fba21f62ddd8e 100644 (file)
--- a/src/detect-engine-port.c
+++ b/src/detect-engine-port.c
@@ -807,6 +807,7 @@ static int DetectPortParseDo(const DetectEngineCtx *de_ctx,
         } else if (!o_set && s[u] == '!') {
             SCLogDebug("negation encountered");
             n_set = 1;
+            BUG_ON(x == 0); /* always false; added to guide static code analyzers like Coverity */
             x--;
         } else if (s[u] == '[') {
             if (!o_set) {