Skip to content

[clang][index] Handle undefined function-like macros in single file parse mode #135054

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
merged 1 commit into from
Apr 9, 2025
Merged

[clang][index] Handle undefined function-like macros in single file parse mode #135054

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
10 changes: 10 additions & 0 deletions clang/lib/Lex/PPExpressions.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,7 @@
#include "clang/Lex/MacroInfo.h"
#include "clang/Lex/PPCallbacks.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Lex/PreprocessorOptions.h"
#include "clang/Lex/Token.h"
#include "llvm/ADT/APSInt.h"
#include "llvm/ADT/STLExtras.h"
Expand Down Expand Up @@ -592,6 +593,15 @@ static bool EvaluateDirectiveSubExpr(PPValue &LHS, unsigned MinPrec,
Token &PeekTok, bool ValueLive,
bool &IncludedUndefinedIds,
Preprocessor &PP) {
if (PP.getPreprocessorOpts().SingleFileParseMode && IncludedUndefinedIds) {
// The single-file parse mode behavior kicks in as soon as single identifier
// is undefined. If we've already seen one, there's no point in continuing
// with the rest of the expression. Besides saving work, this also prevents
// calling undefined function-like macros.
PP.DiscardUntilEndOfDirective(PeekTok);
return true;
}

unsigned PeekPrec = getPrecedence(PeekTok.getKind());
// If this token isn't valid, report the error.
if (PeekPrec == ~0U) {
Expand Down
15 changes: 15 additions & 0 deletions clang/test/Index/single-file-parse-undefined-function-like-macro.c
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,15 @@
// RUN: split-file %s %t
// RUN: c-index-test -single-file-parse %t/tu.c 2>&1 | FileCheck %t/tu.c

//--- header.h
#define FUNCTION_LIKE_MACRO() 1
//--- tu.c
#include "header.h"
// CHECK-NOT: tu.c:[[@LINE+1]]:5: error: function-like macro 'FUNCTION_LIKE_MACRO' is not defined
#if FUNCTION_LIKE_MACRO()
// CHECK: tu.c:[[@LINE+1]]:5: FunctionDecl=then_fn
int then_fn();
#else
// CHECK: tu.c:[[@LINE+1]]:5: FunctionDecl=else_fn
int else_fn();
#endif
Loading