From 0ebca2b10fa814cc11f8145261e77f3beb0c0bf8 Mon Sep 17 00:00:00 2001
From: Sebastian Pipping <sebastian@pipping.org>
Date: Fri, 12 Jan 2024 00:34:54 +0100
Subject: [PATCH] examples/element_declarations.c: Fix memleak in
 dumpContentModel on OOM

clang-tidy output was:
> [..]/examples/element_declarations.c:163:16: warning: Potential leak of memory pointed to by 'stackTop' [clang-analyzer-unix.Malloc]
>   163 |         return false;
>       |                ^
---
 expat/examples/element_declarations.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/expat/examples/element_declarations.c b/expat/examples/element_declarations.c
index 437b0996..c6c9105e 100644
--- a/expat/examples/element_declarations.c
+++ b/expat/examples/element_declarations.c
@@ -157,11 +157,17 @@ dumpContentModel(const XML_Char *name, const XML_Content *root) {
     stackTop = stackPopFree(stackTop);
 
     for (size_t u = model->numchildren; u >= 1; u--) {
-      stackTop
+      Stack *const newStackTop
           = stackPushMalloc(stackTop, model->children + (u - 1), level + 1);
-      if (! stackTop) {
+      if (! newStackTop) {
+        // We ran out of memory, so let's free all memory allocated
+        // earlier in this function, to be leak-clean:
+        while (stackTop != NULL) {
+          stackTop = stackPopFree(stackTop);
+        }
         return false;
       }
+      stackTop = newStackTop;
     }
   }