[clang] Fix crash when an attribute is applied to pragma attribute/pragma dump (PR #137880)

[Erich Keane via cfe-commits]

https://github.com/erichkeane updated https://github.com/llvm/llvm-project/pull/137880

>From be6d7e3fcf4ef53bdf0dce7ff1b541f9de33c81f Mon Sep 17 00:00:00 2001
From: erichkeane <ekeane at nvidia.com>
Date: Tue, 29 Apr 2025 14:32:32 -0700
Subject: [PATCH 1/2] Fix crash when an attribute is applied to pragma
 attribute/pragma dump

These two don't result in a statement, so the attempt to apply the
attributes to them was crashing.  This patch correctly prohibits the use
of attributes on these clauses.

Fixes: #137861
---
 clang/lib/Parse/ParseStmt.cpp  |  4 ++++
 clang/test/Parser/gh137861.cpp | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)
 create mode 100644 clang/test/Parser/gh137861.cpp

diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp
index 4e801f4ef890f..97924f093240f 100644
--- a/clang/lib/Parse/ParseStmt.cpp
+++ b/clang/lib/Parse/ParseStmt.cpp
@@ -526,10 +526,14 @@ StmtResult Parser::ParseStatementOrDeclarationAfterAttributes(
     return ParsePragmaLoopHint(Stmts, StmtCtx, TrailingElseLoc, CXX11Attrs);
 
   case tok::annot_pragma_dump:
+    ProhibitAttributes(CXX11Attrs);
+    ProhibitAttributes(GNUAttrs);
     HandlePragmaDump();
     return StmtEmpty();
 
   case tok::annot_pragma_attribute:
+    ProhibitAttributes(CXX11Attrs);
+    ProhibitAttributes(GNUAttrs);
     HandlePragmaAttribute();
     return StmtEmpty();
   }
diff --git a/clang/test/Parser/gh137861.cpp b/clang/test/Parser/gh137861.cpp
new file mode 100644
index 0000000000000..9354aef919650
--- /dev/null
+++ b/clang/test/Parser/gh137861.cpp
@@ -0,0 +1,33 @@
+// RUN: %clang_cc1 %s -verify 
+
+void foo() {
+  // expected-error at +1{{an attribute list cannot appear here}}
+__attribute__((aligned(64)))
+#pragma clang attribute push(__attribute__((uninitialized)), apply_to = any(variable(is_local)))
+{
+  int f;
+}
+#pragma clang attribute pop
+}
+
+void foo2() {
+  // expected-error at +1{{an attribute list cannot appear here}}
+__attribute__((aligned(64)))
+#pragma clang __debug dump foo
+}
+
+void foo3() {
+  // expected-error at +1{{an attribute list cannot appear here}}
+  [[nodiscard]]
+#pragma clang attribute push(__attribute__((uninitialized)), apply_to = any(variable(is_local)))
+{
+  int f;
+}
+#pragma clang attribute pop
+}
+
+void foo4() {
+  // expected-error at +1{{an attribute list cannot appear here}}
+  [[nodiscard]]
+#pragma clang __debug dump foo
+}

>From 5411b1fb7ea982898b29bdfbe59faaab390e7bb9 Mon Sep 17 00:00:00 2001
From: erichkeane <ekeane at nvidia.com>
Date: Wed, 30 Apr 2025 06:26:27 -0700
Subject: [PATCH 2/2] add release note

---
 clang/docs/ReleaseNotes.rst | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 3105d8b481560..8f6a191c6a375 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -471,6 +471,9 @@ Bug Fixes in This Version
   evaluation. The crashes were happening during diagnostics emission due to
   unimplemented statement printer. (#GH132641)
 - Fixed visibility calculation for template functions. (#GH103477)
+- Fixed a bug where an attribute before a ``pragma clang attribute`` or
+  ``pragma clang __debug`` would cause an assertion. Instead, this now diagnoses
+  the invalid attribute location appropriately.  (#GH137861)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^