From: John McCall <rjmccall@apple.com>
Date: Wed, 20 Jun 2012 21:58:02 +0000 (+0000)
Subject: Introduce ObjCRuntime::hasWeakClassImport() and use it in the appropriate
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0b92fcb1353d2d8b31b6c485e6caa14568aca43b;p=clang

Introduce ObjCRuntime::hasWeakClassImport() and use it in the appropriate
places.  I've turned this off for the GNU runtimes --- I don't know if
they support weak class import, but it's easy enough for them to opt in.

Also tweak a comment per review by Jordan.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158860 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/ObjCRuntime.h b/include/clang/Basic/ObjCRuntime.h
index b87632ff6a..a1024c4a58 100644
--- a/include/clang/Basic/ObjCRuntime.h
+++ b/include/clang/Basic/ObjCRuntime.h
@@ -160,6 +160,18 @@ public:
     llvm_unreachable("bad kind");
   }
 
+  /// Does this runtime support weakly importing classes?
+  bool hasWeakClassImport() const {
+    switch (getKind()) {
+    case MacOSX: return true;
+    case iOS: return true;
+    case FragileMacOSX: return false;
+    case FragileGNU: return false;
+    case GNU: return false;
+    }
+    llvm_unreachable("bad kind");
+  }
+
   /// Try to parse an Objective-C runtime specification from the given string.
   ///
   /// Return true on error.
diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index 7d72093700..574f779b86 100644
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -430,7 +430,7 @@ bool Decl::canBeWeakImported(bool &IsDefinition) const {
 
   // Objective-C classes, if this is the non-fragile runtime.
   } else if (isa<ObjCInterfaceDecl>(this) &&
-             getASTContext().getLangOpts().ObjCRuntime.isNonFragile()) {
+             getASTContext().getLangOpts().ObjCRuntime.hasWeakClassImport()) {
     return true;
 
   // Nothing else.
diff --git a/lib/Basic/ObjCRuntime.cpp b/lib/Basic/ObjCRuntime.cpp
index d92adbcb46..d66da0706f 100644
--- a/lib/Basic/ObjCRuntime.cpp
+++ b/lib/Basic/ObjCRuntime.cpp
@@ -43,8 +43,9 @@ bool ObjCRuntime::tryParse(StringRef input) {
   // Look for the last dash.
   std::size_t dash = input.rfind('-');
 
-  // We permit (1) dashes in the runtime name and (2) the version to
-  // be omitted, so ignore dashes that aren't followed by a digit.
+  // We permit dashes in the runtime name, and we also permit the
+  // version to be omitted, so if we see a dash not followed by a
+  // digit then we need to ignore it.
   if (dash != StringRef::npos && dash + 1 != input.size() &&
       (input[dash+1] < '0' || input[dash+1] > '9')) {
     dash = StringRef::npos;
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 826fa03621..a5337867b1 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -644,7 +644,7 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
            .Case("objc_instancetype", LangOpts.ObjC2)
            .Case("objc_modules", LangOpts.ObjC2 && LangOpts.Modules)
            .Case("objc_nonfragile_abi", LangOpts.ObjCRuntime.isNonFragile())
-           .Case("objc_weak_class", LangOpts.ObjCRuntime.isNonFragile())
+           .Case("objc_weak_class", LangOpts.ObjCRuntime.hasWeakClassImport())
            .Case("ownership_holds", true)
            .Case("ownership_returns", true)
            .Case("ownership_takes", true)