Add an option to emulate the strange Apple gcc behavior of #pragma pack.

<rdar://problem/10374763>



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143527 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 0 deletions

diff --git a/lib/Parse/ParsePragma.cpp b/lib/Parse/ParsePragma.cpp
index 2ccb6ea88d..2069d31dd2 100644
--- a/lib/Parse/ParsePragma.cpp
+++ b/lib/Parse/ParsePragma.cpp
@@ -110,6 +110,12 @@ void PragmaPackHandler::HandlePragma(Preprocessor &PP,
       return;
 
     PP.Lex(Tok);
+
+    // In MSVC/gcc, #pragma pack(4) sets the alignment without affecting
+    // the push/pop stack.
+    // In Apple gcc, #pragma pack(4) is equivalent to #pragma pack(push, 4)
+    if (PP.getLangOptions().ApplePragmaPack)
+      Kind = Sema::PPK_Push;
   } else if (Tok.is(tok::identifier)) {
     const IdentifierInfo *II = Tok.getIdentifierInfo();
     if (II->isStr("show")) {
@@ -159,6 +165,11 @@ void PragmaPackHandler::HandlePragma(Preprocessor &PP,
         }
       }
     }
+  } else if (PP.getLangOptions().ApplePragmaPack) {
+    // In MSVC/gcc, #pragma pack() resets the alignment without affecting
+    // the push/pop stack.
+    // In Apple gcc #pragma pack() is equivalent to #pragma pack(pop).
+    Kind = Sema::PPK_Pop;
   }
 
   if (Tok.isNot(tok::r_paren)) {