From 5f09d535dbad502171247797061e578b1b86ea8e Mon Sep 17 00:00:00 2001
From: chrchr-github <christian.riesch@live.com>
Date: Thu, 11 Jul 2024 23:37:36 +0200
Subject: [PATCH] Fix  #9657 FP on missing va_end() after non-returning
 function

---
 lib/checkvaarg.cpp | 19 +++++++++++++++++--
 test/testvaarg.cpp | 16 ++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/lib/checkvaarg.cpp b/lib/checkvaarg.cpp
index 7ad381e16d0..8b0f3d87145 100644
--- a/lib/checkvaarg.cpp
+++ b/lib/checkvaarg.cpp
@@ -144,9 +144,24 @@ void CheckVaarg::va_list_usage()
                 }
                 open = nopen;
                 tok = tok->linkAt(1);
-            } else if (Token::Match(tok, "throw|return"))
+            } else if (Token::Match(tok, "throw|return") || (Token::Match(tok, "%name% (") && mSettings->library.isnoreturn(tok))) {
                 exitOnEndOfStatement = true;
-            else if (tok->str() == "break") {
+                if (var->scope() == tok->scope()) {
+                    if (const Token* tok3 = Token::findmatch(tok->next(), "%varid%|;", var->declarationId())) {
+                        bool bail = tok3->str() == ";";
+                        if (!bail) {
+                            int argn{};
+                            if (const Token* ftok = getTokenArgumentFunction(tok3, argn)) {
+                                bail = ftok->str() != "va_arg";
+                            }
+                        }
+                        if (bail) {
+                            open = false;
+                            break;
+                        }
+                    }
+                }
+            } else if (tok->str() == "break") {
                 tok = findNextTokenFromBreak(tok);
                 if (!tok)
                     return;
diff --git a/test/testvaarg.cpp b/test/testvaarg.cpp
index f4a42a4a111..7d94ff2cb75 100644
--- a/test/testvaarg.cpp
+++ b/test/testvaarg.cpp
@@ -309,6 +309,22 @@ class TestVaarg : public TestFixture {
               "format_err:\n"
               "}");
         ASSERT_EQUALS("", errout_str());
+
+        // #9657
+        check("static void __attribute__((__noreturn__)) __attribute__((__format__(__printf__, 1, 0)))\n"
+              "    notreturning(const char* fmt, va_list args) {\n"
+              "    va_list args_copy;\n"
+              "    va_copy(args_copy, args);\n"
+              "    vprintf(fmt, args_copy);\n"
+              "    va_end(args_copy);\n"
+              "    exit(1);\n"
+              "}\n"
+              "static void check_noret_va_end(const char* fmt, ...) {\n"
+              "    va_list args;\n"
+              "    va_start(args, fmt);\n"
+              "    notreturning(fmt, args);\n"
+              "}\n");
+        ASSERT_EQUALS("", errout_str());
     }
 
     void va_start_subsequentCalls() {