From 6947e112a82311ae16c7db4010f2fa5bc57dd045 Mon Sep 17 00:00:00 2001
From: Anton Lindqvist <anton@basename.se>
Date: Wed, 11 Dec 2024 20:32:07 +0100
Subject: [PATCH] Ignore knownConditionTrueFalse in static assertions

_Static_assert (deprecated in C23) should be treated like static_assert.
---
 lib/checkother.cpp | 8 +++++++-
 test/testother.cpp | 6 ++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/checkother.cpp b/lib/checkother.cpp
index 1b4cb0e1393..8acc294fdc3 100644
--- a/lib/checkother.cpp
+++ b/lib/checkother.cpp
@@ -2574,6 +2574,12 @@ namespace {
     }
 }
 
+static bool
+isStaticAssert(const Token *tok)
+{
+    return Token::Match(tok, "_Static_assert|static_assert (");
+}
+
 void CheckOther::checkDuplicateExpression()
 {
     {
@@ -2700,7 +2706,7 @@ void CheckOther::checkDuplicateExpression()
                                     while (parent && parent->astParent()) {
                                         parent = parent->astParent();
                                     }
-                                    if (parent && parent->previous() && parent->strAt(-1) == "static_assert") {
+                                    if (parent && isStaticAssert(parent->previous())) {
                                         continue;
                                     }
                                 }
diff --git a/test/testother.cpp b/test/testother.cpp
index 3eeb3089b79..b5a62935ec8 100644
--- a/test/testother.cpp
+++ b/test/testother.cpp
@@ -6917,6 +6917,12 @@ class TestOther : public TestFixture {
               "}");
         ASSERT_EQUALS("", errout_str());
 
+        check("void f() {\n"
+              "    enum { Four = 4 };\n"
+              "    _Static_assert(Four == 4, \"\");\n"
+              "}");
+        ASSERT_EQUALS("", errout_str());
+
         check("void f() {\n"
               "    enum { Four = 4 };\n"
               "    static_assert(4 == Four, \"\");\n"