[clang] [Clang] Fix assertion failure in SDiagsWriter when finish() is not called (PR #181712)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: mitchell (zeyi2)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/181712.diff


3 Files Affected:

- (modified) clang/docs/ReleaseNotes.rst (+1) 
- (modified) clang/lib/Frontend/SerializedDiagnosticPrinter.cpp (+4-1) 
- (added) clang/test/Tooling/serialize-diagnostics.cpp (+6) 


``````````diff
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 6063c3fbf48c8..01da9a3104e2f 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -265,6 +265,7 @@ Bug Fixes in This Version
 - Clang now outputs relative paths of embeds for dependency output. (#GH161950)
 - Fixed an assertion failure when evaluating ``_Countof`` on invalid ``void``-typed operands. (#GH180893)
 - Fixed a ``-Winvalid-noreturn`` false positive for unreachable ``try`` blocks following an unconditional ``throw``. (#GH174822)
+- Fixed an assertion failure in the serialized diagnostic printer when it is destroyed without calling ``finish()``. (#GH140433)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp b/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp
index 1dffe7cb2b9f0..fe2dca090b09e 100644
--- a/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp
+++ b/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp
@@ -146,7 +146,10 @@ class SDiagsWriter : public DiagnosticConsumer {
     EmitPreamble();
   }
 
-  ~SDiagsWriter() override {}
+  ~SDiagsWriter() override {
+    if (OriginalInstance && !IsFinishing)
+      finish();
+  }
 
   void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
                         const Diagnostic &Info) override;
diff --git a/clang/test/Tooling/serialize-diagnostics.cpp b/clang/test/Tooling/serialize-diagnostics.cpp
new file mode 100644
index 0000000000000..fbf5554fc90a2
--- /dev/null
+++ b/clang/test/Tooling/serialize-diagnostics.cpp
@@ -0,0 +1,6 @@
+// RUN: clang-check %s -- -Wunknown-warning-option --serialize-diagnostics %t.dia 2>&1 | FileCheck %s --allow-empty
+// RUN: ls %t.dia
+
+int main() {
+  return 0;
+}

``````````

</details>


https://github.com/llvm/llvm-project/pull/181712