================
@@ -881,6 +886,35 @@ diagnoseFrameworkInclude(DiagnosticsEngine &Diags,
SourceLocation IncludeLoc,
<< IncludeFilename;
}
+/// Return true if a shadow has been detected and the caller should
+/// stop and return the first-found file and module, false otherwise.
+static bool checkAndStoreCandidate(
+ ModuleMap::KnownHeader *SuggestedModule, OptionalFileEntryRef
CandidateFile,
+ StringRef CandidateDir, DiagnosticsEngine &Diags, StringRef Filename,
+ SourceLocation IncludeLoc, ModuleMap::KnownHeader &FirstModule,
+ OptionalFileEntryRef &FirstHeader, SmallString<1024> &FirstDir) {
+ if (!FirstHeader) {
+ // Found the first candidate
+ FirstHeader = CandidateFile;
+ FirstDir = CandidateDir;
+ if (SuggestedModule)
+ FirstModule = *SuggestedModule;
+ return false;
+ }
+
+ if (FirstDir != CandidateDir) {
+ // Found a second candidate from a different directory
+ Diags.Report(IncludeLoc, diag::warn_header_shadowed)
+ << Filename << FirstDir << CandidateDir;
+ if (SuggestedModule)
+ *SuggestedModule = FirstModule;
+ return true;
+ }
+
+ // Found a candidate from the same directory as the first one
+ return false;
----------------
Jinjie-Huang wrote:
Thanks for review. Based on the code implementation and my testing, it appears
that although the search paths themselves are deduplicated, the current
baseline implementation executes two search strategies simultaneously:
1. MSVC rule (not corrected) for "quoted search": This strategy searches
based on the include stack, checking each directory level in the stack. For
example, in ./x.cpp -> a/a.h -> a/b.h, when searching for b.h, it first looks
in the paths "a" and ".". These paths are represented in the code by
"Includers".
[code](https://github.com/llvm/llvm-project/blob/main/clang/lib/Lex/HeaderSearch.cpp#L939-L1016)
2. Regular gcc/clang rule: This constructs search paths by combining the
provided -I lists and system paths.
[code](https://github.com/llvm/llvm-project/blob/main/clang/lib/Lex/HeaderSearch.cpp#L1074-L1139)
Therefore, when paths from strategy 1 and strategy 2 happen to be identical,
this case can occur.
The current implementation of this diagnostic does not return immediately upon
the first finding. Its purpose is to check if a header file with the same name
exists anywhere within the combined set of paths from strategies 1 and 2. This
check avoids false positives that could arise if, for instance, a/b.his found
in strategy 1 (Includers) and then another b.h is found in an -I a from
strategy 2.
https://github.com/llvm/llvm-project/pull/162491
_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
