Skip to content

[Clang] Do not warn for serialized builtin or command-line definitions #137306

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
jmmartinez merged 2 commits into from
May 1, 2025
Merged

[Clang] Do not warn for serialized builtin or command-line definitions #137306

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
5a0da33
Pre-commit test: [Clang] Do not warn for serialized builtin or comman…
jmmartinez Apr 25, 2025
40812df
[Clang] Do not warn for serialized builtin or command-line definitions
jmmartinez Apr 25, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 6 additions & 2 deletions clang/lib/Lex/PPDirectives.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -371,8 +371,12 @@ bool Preprocessor::CheckMacroName(Token &MacroNameTok, MacroUse isDefineUndef,
SourceLocation MacroNameLoc = MacroNameTok.getLocation();
if (ShadowFlag)
*ShadowFlag = false;
if (!SourceMgr.isInSystemHeader(MacroNameLoc) &&
(SourceMgr.getBufferName(MacroNameLoc) != "<built-in>")) {
// Macro names with reserved identifiers are accepted if built-in or passed
// through the command line (the later may be present if -dD was used to
// generate the preprocessed file).
bool IsBuiltinOrCmd = SourceMgr.isWrittenInBuiltinFile(MacroNameLoc) ||
SourceMgr.isWrittenInCommandLineFile(MacroNameLoc);
Copy link
Contributor

@nikic nikic May 1, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Can at least combine these to avoid the duplicate getPresumedLoc(), but possibly these can be more efficient in general? E.g. isInSystemHeader has a much more optimized implementation.

if (!IsBuiltinOrCmd && !SourceMgr.isInSystemHeader(MacroNameLoc)) {
MacroDiag D = MD_NoWarn;
if (isDefineUndef == MU_Define) {
D = shouldWarnOnMacroDef(*this, II);
Expand Down
11 changes: 11 additions & 0 deletions clang/test/Preprocessor/macro_reserved.i
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
// RUN: %clang_cc1 -fsyntax-only -verify -x cpp-output %s
#pragma clang diagnostic push
#pragma clang diagnostic warning "-Wreserved-macro-identifier"
# 1 "<built-in>" 1
#define __BUILTIN__
# 2 "<command line>" 1
#define __CMD__
# 3 "biz.cpp" 1
#define __SOME_FILE__ // expected-warning {{macro name is a reserved identifier}}
int v;
#pragma clang diagnostic pop
Loading