vendor/llvm/llvm-trunk-r321017

1 files changed, 30 insertions, 7 deletions

diff --git a/lib/Object/COFFModuleDefinition.cpp b/lib/Object/COFFModuleDefinition.cpp
index 510eac8b239ba..a571354648d65 100644
--- a/lib/Object/COFFModuleDefinition.cpp
+++ b/lib/Object/COFFModuleDefinition.cpp
@@ -57,9 +57,27 @@ struct Token {
 };
 
 static bool isDecorated(StringRef Sym, bool MingwDef) {
-  // mingw does not prepend "_".
-  return (!MingwDef && Sym.startswith("_")) || Sym.startswith("@") ||
-         Sym.startswith("?");
+  // In def files, the symbols can either be listed decorated or undecorated.
+  //
+  // - For cdecl symbols, only the undecorated form is allowed.
+  // - For fastcall and vectorcall symbols, both fully decorated or
+  //   undecorated forms can be present.
+  // - For stdcall symbols in non-MinGW environments, the decorated form is
+  //   fully decorated with leading underscore and trailing stack argument
+  //   size - like "_Func@0".
+  // - In MinGW def files, a decorated stdcall symbol does not include the
+  //   leading underscore though, like "Func@0".
+
+  // This function controls whether a leading underscore should be added to
+  // the given symbol name or not. For MinGW, treat a stdcall symbol name such
+  // as "Func@0" as undecorated, i.e. a leading underscore must be added.
+  // For non-MinGW, look for '@' in the whole string and consider "_Func@0"
+  // as decorated, i.e. don't add any more leading underscores.
+  // We can't check for a leading underscore here, since function names
+  // themselves can start with an underscore, while a second one still needs
+  // to be added.
+  return Sym.startswith("@") || Sym.contains("@@") || Sym.startswith("?") ||
+         (!MingwDef && Sym.contains('@'));
 }
 
 static Error createError(const Twine &Err) {
@@ -99,7 +117,7 @@ public:
       return Token(Identifier, S);
     }
     default: {
-      size_t End = Buf.find_first_of("=,\r\n \t\v");
+      size_t End = Buf.find_first_of("=,;\r\n \t\v");
       StringRef Word = Buf.substr(0, End);
       Kind K = llvm::StringSwitch<Kind>(Word)
                    .Case("BASE", KwBase)
@@ -232,13 +250,18 @@ private:
     for (;;) {
       read();
       if (Tok.K == Identifier && Tok.Value[0] == '@') {
-        if (Tok.Value.drop_front().getAsInteger(10, E.Ordinal)) {
-          // Not an ordinal modifier at all, but the next export (fastcall
-          // decorated) - complete the current one.
+        if (Tok.Value == "@") {
+          // "foo @ 10"
+          read();
+          Tok.Value.getAsInteger(10, E.Ordinal);
+        } else if (Tok.Value.drop_front().getAsInteger(10, E.Ordinal)) {
+          // "foo \n @bar" - Not an ordinal modifier at all, but the next
+          // export (fastcall decorated) - complete the current one.
           unget();
           Info.Exports.push_back(E);
           return Error::success();
         }
+        // "foo @10"
         read();
         if (Tok.K == KwNoname) {
           E.Noname = true;