[modules] Replace `-Wauto-import` with `-Rmodule-include-translation`.

Diagnostic for `-Wauto-import` shouldn't be a warning because it doesn't
represent a potential problem in code that should be fixed. And the
emitted fix-it is likely to trigger `-Watimport-in-framework-header`
which makes it challenging to have a warning-free codebase. But it is
still useful to see how include directives are translated into modular
imports and which module a header belongs to, that's why keep it as a remark.

Keep `-Wauto-import` for now to allow a gradual migration for codebases
using `-Wno-auto-import`, e.g., `-Weverything -Wno-auto-import`.

rdar://79594287

Differential Revision: https://reviews.llvm.org/D130138

1 files changed, 3 insertions, 15 deletions

diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index 352e1f2..4679cb4 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -1806,22 +1806,14 @@ static void diagnoseAutoModuleImport(
     Preprocessor &PP, SourceLocation HashLoc, Token &IncludeTok,
     ArrayRef<std::pair<IdentifierInfo *, SourceLocation>> Path,
     SourceLocation PathEnd) {
-  StringRef ImportKeyword;
-  if (PP.getLangOpts().ObjC)
-    ImportKeyword = "@import";
-  else if (PP.getLangOpts().ModulesTS || PP.getLangOpts().CPlusPlusModules)
-    ImportKeyword = "import";
-  else
-    return; // no import syntax available
-
   SmallString<128> PathString;
   for (size_t I = 0, N = Path.size(); I != N; ++I) {
     if (I)
       PathString += '.';
     PathString += Path[I].first->getName();
   }
-  int IncludeKind = 0;
 
+  int IncludeKind = 0;
   switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
   case tok::pp_include:
     IncludeKind = 0;
@@ -1843,12 +1835,8 @@ static void diagnoseAutoModuleImport(
     llvm_unreachable("unknown include directive kind");
   }
 
-  CharSourceRange ReplaceRange(SourceRange(HashLoc, PathEnd),
-                               /*IsTokenRange=*/false);
-  PP.Diag(HashLoc, diag::warn_auto_module_import)
-      << IncludeKind << PathString
-      << FixItHint::CreateReplacement(
-             ReplaceRange, (ImportKeyword + " " + PathString + ";").str());
+  PP.Diag(HashLoc, diag::remark_pp_include_directive_modular_translation)
+      << IncludeKind << PathString;
 }
 
 // Given a vector of path components and a string containing the real