1 files changed, 14 insertions, 1 deletions
diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index a69c4dbb3a2..3b53d07cc4a 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -29,6 +29,7 @@
 #include "clang/Lex/MacroInfo.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/PreprocessorLexer.h"
+#include "clang/Lex/PreprocessorOptions.h"
 #include "clang/Lex/Token.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
@@ -1450,6 +1451,17 @@ static bool isTargetEnvironment(const TargetInfo &TI,
   return TI.getTriple().getEnvironment() == Env.getEnvironment();
 }
 
+static void remapMacroPath(
+    SmallString<256> &Path,
+    const std::map<std::string, std::string, std::greater<std::string>>
+        &MacroPrefixMap) {
+  for (const auto &Entry : MacroPrefixMap)
+    if (llvm::sys::path::replace_path_prefix(Path, Entry.first, Entry.second,
+                                             llvm::sys::path::Style::native,
+                                             true))
+      break;
+}
+
 /// ExpandBuiltinMacro - If an identifier token is read that is to be expanded
 /// as a builtin macro, handle it and return the next token as 'Tok'.
 void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
@@ -1516,7 +1528,7 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
     }
 
     // Escape this filename.  Turn '\' -> '\\' '"' -> '\"'
-    SmallString<128> FN;
+    SmallString<256> FN;
     if (PLoc.isValid()) {
       // __FILE_NAME__ is a Clang-specific extension that expands to the
       // the last part of __FILE__.
@@ -1532,6 +1544,7 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
         FN += PLoc.getFilename();
       }
       Lexer::Stringify(FN);
+      remapMacroPath(FN, PPOpts->MacroPrefixMap);
       OS << '"' << FN << '"';
     }
     Tok.setKind(tok::string_literal);