[clang] [clang][analyzer] Fixed 'if_nameindex' in MallocChecker (PR #207726)

[via cfe-commits]

llvmorg-github-actions[bot] wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Balázs Kéri (balazske)

<details>
<summary>Changes</summary>

The function `if_nameindex` has 0 arguments but `MallocChecker` expected it to have 1 argument and was not recognized by the checker correctly.

---
Full diff: https://github.com/llvm/llvm-project/pull/207726.diff


2 Files Affected:

- (modified) clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp (+1-1) 
- (modified) clang/test/Analysis/malloc-failure.c (+1-1) 


``````````diff
diff --git a/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 7ea028246a2ee..287824984623c 100644
--- a/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -547,7 +547,7 @@ class MallocChecker
       {{CDM::CLibrary, {"strdup"}, 1}, &MallocChecker::checkStrdup},
       {{CDM::CLibrary, {"_strdup"}, 1}, &MallocChecker::checkStrdup},
       {{CDM::CLibrary, {"kmalloc"}, 2}, &MallocChecker::checkKernelMalloc},
-      {{CDM::CLibrary, {"if_nameindex"}, 1}, &MallocChecker::checkIfNameIndex},
+      {{CDM::CLibrary, {"if_nameindex"}, 0}, &MallocChecker::checkIfNameIndex},
       {{CDM::CLibrary, {"wcsdup"}, 1}, &MallocChecker::checkStrdup},
       {{CDM::CLibrary, {"_wcsdup"}, 1}, &MallocChecker::checkStrdup},
       {{CDM::CLibrary, {"g_malloc"}, 1}, &MallocChecker::checkBasicAlloc},
diff --git a/clang/test/Analysis/malloc-failure.c b/clang/test/Analysis/malloc-failure.c
index bf421fe7672c8..aea58dad470fa 100644
--- a/clang/test/Analysis/malloc-failure.c
+++ b/clang/test/Analysis/malloc-failure.c
@@ -71,6 +71,6 @@ void test_strdup() {
 
 void test_ifnameindex() {
   struct if_nameindex *p = if_nameindex();
-  p->x = 1; //FIXME: if_nameindex is not recognized by the checker
+  p->x = 1; //expected-warning{{dereference of a null pointer}}
   if_freenameindex(p);
 }

``````````

</details>


https://github.com/llvm/llvm-project/pull/207726