[clang] 5c27407 - [analyzer] Suppress optin.cplusplus.VirtualCall warnings in system headers (#184183)

[via cfe-commits]

Author: Tarun Thammisetty
Date: 2026-03-04T13:56:47Z
New Revision: 5c274078422435b1c666d99375e958d30c4b77a6

URL: https://github.com/llvm/llvm-project/commit/5c274078422435b1c666d99375e958d30c4b77a6
DIFF: https://github.com/llvm/llvm-project/commit/5c274078422435b1c666d99375e958d30c4b77a6.diff

LOG: [analyzer] Suppress optin.cplusplus.VirtualCall warnings in system headers (#184183)

Fixes #184178

The optin.cplusplus.VirtualCall checker reports warnings for virtual
method calls during construction/destruction even when the call site is
in a system header (included via -isystem). Users cannot fix such code
and must resort to NOLINT suppressions.

Add a system header check in checkPreCall before emitting the report,
consistent with how other checkers (e.g. MallocChecker) handle this.

Added: 
    clang/test/Analysis/Inputs/virtualcall-system-header.h

Modified: 
    clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
    clang/test/Analysis/virtualcall.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
index 6c27f58d308aa..160fc2596e485 100644
--- a/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
@@ -118,6 +118,11 @@ void VirtualCallChecker::checkPreCall(const CallEvent &Call,
   if (!isVirtualCall(CE))
     return;
 
+  // Don't warn about virtual calls in system headers (e.g. libraries included
+  // via -isystem), as the user has no control over such code.
+  if (C.getSourceManager().isInSystemHeader(CE->getBeginLoc()))
+    return;
+
   const MemRegion *Reg = MC->getCXXThisVal().getAsRegion();
   const ObjectState *ObState = State->get<CtorDtorMap>(Reg);
   if (!ObState)

diff  --git a/clang/test/Analysis/Inputs/virtualcall-system-header.h b/clang/test/Analysis/Inputs/virtualcall-system-header.h
new file mode 100644
index 0000000000000..2cdde63677364
--- /dev/null
+++ b/clang/test/Analysis/Inputs/virtualcall-system-header.h
@@ -0,0 +1,11 @@
+#pragma clang system_header
+
+struct SysBase {
+  virtual void shutdown() = 0;
+  virtual ~SysBase() = default;
+};
+
+struct SysService : SysBase {
+  void shutdown() override {}
+  ~SysService() override { shutdown(); } // no-warning
+};

diff  --git a/clang/test/Analysis/virtualcall.cpp b/clang/test/Analysis/virtualcall.cpp
index 82285b6d12844..ebbfe3c1f9d90 100644
--- a/clang/test/Analysis/virtualcall.cpp
+++ b/clang/test/Analysis/virtualcall.cpp
@@ -11,7 +11,12 @@
 // RUN:                    -analyzer-checker=debug.ExprInspection \
 // RUN:                    -std=c++11 -verify=pure,impure -std=c++11 %s
 
+// Verify no warnings for virtual calls in system headers.
+// RUN: %clang_analyze_cc1 -analyzer-checker=core,optin.cplusplus.VirtualCall \
+// RUN:                    -std=c++11 -verify=system,impure %s
+
 #include "virtualcall.h"
+#include "Inputs/virtualcall-system-header.h"
 
 void clang_analyzer_warnIfReached();