Index: clang/include/clang/Basic/DiagnosticLexKinds.td =================================================================== --- clang/include/clang/Basic/DiagnosticLexKinds.td +++ clang/include/clang/Basic/DiagnosticLexKinds.td @@ -391,6 +391,7 @@ "empty macro arguments are incompatible with C++98">, InGroup, DefaultIgnore; def note_macro_here : Note<"macro %0 defined here">; +def note_macro_expansion_here : Note<"expansion of macro %0 requested here">; def err_pp_opencl_variadic_macros : Error<"variadic macros not supported in OpenCL">; Index: clang/include/clang/Lex/Preprocessor.h =================================================================== --- clang/include/clang/Lex/Preprocessor.h +++ clang/include/clang/Lex/Preprocessor.h @@ -173,6 +173,9 @@ IdentifierInfo *Ident__is_target_os; // __is_target_os IdentifierInfo *Ident__is_target_environment; // __is_target_environment + // Weak, only valid (and set) while InMacroArgs is true. + Token* ArgMacro; + SourceLocation DATELoc, TIMELoc; // Next __COUNTER__ value, starts at 0. Index: clang/lib/Lex/PPDirectives.cpp =================================================================== --- clang/lib/Lex/PPDirectives.cpp +++ clang/lib/Lex/PPDirectives.cpp @@ -886,6 +886,8 @@ case tok::pp___include_macros: case tok::pp_pragma: Diag(Result, diag::err_embedded_directive) << II->getName(); + Diag(*ArgMacro, diag::note_macro_expansion_here) + << ArgMacro->getIdentifierInfo(); DiscardUntilEndOfDirective(); return; default: Index: clang/lib/Lex/PPMacroExpansion.cpp =================================================================== --- clang/lib/Lex/PPMacroExpansion.cpp +++ clang/lib/Lex/PPMacroExpansion.cpp @@ -492,10 +492,13 @@ // Preprocessor directives used inside macro arguments are not portable, and // this enables the warning. InMacroArgs = true; + ArgMacro = &Identifier; + Args = ReadMacroCallArgumentList(Identifier, MI, ExpansionEnd); // Finished parsing args. InMacroArgs = false; + ArgMacro = nullptr; // If there was an error parsing the arguments, bail out. if (!Args) return true; Index: clang/lib/Lex/Preprocessor.cpp =================================================================== --- clang/lib/Lex/Preprocessor.cpp +++ clang/lib/Lex/Preprocessor.cpp @@ -102,6 +102,7 @@ DisableMacroExpansion = false; MacroExpansionInDirectivesOverride = false; InMacroArgs = false; + ArgMacro = nullptr; InMacroArgPreExpansion = false; NumCachedTokenLexers = 0; PragmasEnabled = true; Index: clang/test/Preprocessor/macro_arg_directive.c =================================================================== --- clang/test/Preprocessor/macro_arg_directive.c +++ clang/test/Preprocessor/macro_arg_directive.c @@ -8,7 +8,7 @@ _Static_assert(n == 5, ""); #define M(A) -M( +M( // expected-note {{expansion of macro 'M' requested here}} #pragma pack(pop) // expected-error {{embedding a #pragma directive within macro arguments is not supported}} ) @@ -18,7 +18,7 @@ ({ int result = 0; __VA_ARGS__; if (!result) { fail(#__VA_ARGS__); }; result }) static inline int f(int k) { - return MUNCH( // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{returning 'void'}} + return MUNCH( // expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{returning 'void'}} expected-note {{expansion of macro 'MUNCH' requested here}} if (k < 3) result = 24; else if (k > 4)