From dcb90780817461ba30ced78338b2270fd3307873 Mon Sep 17 00:00:00 2001 From: Jan Svoboda Date: Thu, 10 Apr 2025 12:32:01 -0700 Subject: [PATCH] [clang][index] Skip over `#include UNDEF_IDENT` in single-file-parse mode (#135218) In the 'single-file-parse' mode, seeing `#include UNDEFINED_IDENTIFIER` should not be treated as an error. The identifier might be defined in a header that we decided to skip, resulting in a nonsensical diagnostic from the user point of view. --- clang/lib/Lex/PPDirectives.cpp | 9 +++++++++ clang/test/Index/single-file-parse-include-macro.c | 10 ++++++++++ 2 files changed, 19 insertions(+) create mode 100644 clang/test/Index/single-file-parse-include-macro.c diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp index 0b53524e2364..d97a6e8d64f9 100644 --- a/clang/lib/Lex/PPDirectives.cpp +++ b/clang/lib/Lex/PPDirectives.cpp @@ -2073,6 +2073,15 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc, return; if (FilenameTok.isNot(tok::header_name)) { + if (FilenameTok.is(tok::identifier) && PPOpts.SingleFileParseMode) { + // If we saw #include IDENTIFIER and lexing didn't turn in into a header + // name, it was undefined. In 'single-file-parse' mode, just skip the + // directive without emitting diagnostics - the identifier might be + // normally defined in previously-skipped include directive. + DiscardUntilEndOfDirective(); + return; + } + Diag(FilenameTok.getLocation(), diag::err_pp_expects_filename); if (FilenameTok.isNot(tok::eod)) DiscardUntilEndOfDirective(); diff --git a/clang/test/Index/single-file-parse-include-macro.c b/clang/test/Index/single-file-parse-include-macro.c new file mode 100644 index 000000000000..6b6ecfd76942 --- /dev/null +++ b/clang/test/Index/single-file-parse-include-macro.c @@ -0,0 +1,10 @@ +// RUN: split-file %s %t +// RUN: c-index-test -single-file-parse %t/tu.c 2>&1 | FileCheck --allow-empty %t/tu.c + +//--- header1.h +#define HEADER2_H "header2.h" +//--- header2.h +//--- tu.c +#include "header1.h" +// CHECK-NOT: tu.c:[[@LINE+1]]:10: error: expected "FILENAME" or +#include HEADER2_H