From 71336e837a51986aa12ca7e27e6ae0549d509aec Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Mon, 18 May 2026 22:47:37 -0700
Subject: [PATCH] Pacify GCC 16.1.1 -Wanalyzer-null-dereference

* src/regex-emacs.c (forall_firstchar):
Avoid undefined behavior in the 2nd eassert when !bufp && !pend.
This pacifies GCC 16.1.1 20260501 (Red Hat 16.1.1-1) x86-64
when Emacs is configured with --enable-gcc-warnings.
---
 src/regex-emacs.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/regex-emacs.c b/src/regex-emacs.c
index 7c8ee144257..03c4ba3e4e9 100644
--- a/src/regex-emacs.c
+++ b/src/regex-emacs.c
@@ -3044,8 +3044,7 @@ static bool
 forall_firstchar (struct re_pattern_buffer *bufp, re_char *p, re_char *pend,
                   bool f (re_char *p, void *arg), void *arg)
 {
-  eassert (!bufp || bufp->used);
-  eassert (pend || bufp->used);
+  eassert (bufp ? !!bufp->used : !!pend);
   return forall_firstchar_1 (p, pend,
                              bufp ? bufp->buffer - 1 : p,
                              bufp ? bufp->buffer + bufp->used + 1 : pend,