Clang importer: Don't add duplicate declarations to the Swift lookup tables.

Author: DougGregor

lib/ClangImporter/SwiftLookupTable.cpp

@@ -41,6 +41,16 @@ bool SwiftLookupTable::matchesContext(clang::DeclContext *foundContext,
   return false;
 }
 
+/// Determine whether the new declarations matches an existing declaration.
+static bool matchesExistingDecl(clang::Decl *decl, clang::Decl *existingDecl) {
+  // If the canonical declarations are equivalent, we have a match.
+  if (decl->getCanonicalDecl() == existingDecl->getCanonicalDecl()) {
+    return true;
+  }
+
+  return false;
+}
+
 void SwiftLookupTable::addEntry(DeclName name, clang::NamedDecl *decl) {
   clang::DeclContext *context
     = decl->getDeclContext()->getRedeclContext()->getPrimaryContext();
@@ -64,6 +74,11 @@ void SwiftLookupTable::addEntry(DeclName name, clang::NamedDecl *decl) {
   auto &fullEntries = knownFull->second;
   for (auto &fullEntry : fullEntries) {
     if (fullEntry.Context == context) {
+      // Check whether this entry matches any existing entry.
+      for (auto existingDecl : fullEntry.Decls) {
+        if (matchesExistingDecl(decl, existingDecl)) return;
+      }
+
       fullEntry.Decls.push_back(decl);
       return;
     }

test/IDE/Inputs/swift_name.h

@@ -1,5 +1,15 @@
 #define SWIFT_NAME(X) __attribute__((swift_name(#X)))
 
+#ifndef SWIFT_ENUM_EXTRA
+#  define SWIFT_ENUM_EXTRA
+#endif
+
+#ifndef SWIFT_ENUM
+#  define SWIFT_ENUM(_type, _name)    \
+  enum _name : _type _name;           \
+  enum SWIFT_ENUM_EXTRA _name : _type
+#endif
+
 // Renaming global variables.
 int SNFoo SWIFT_NAME(Bar);
 
@@ -16,6 +26,13 @@ struct SNSomeStruct SNMakeSomeStructForX(double X) SWIFT_NAME(makeSomeStruct(x:)
 // Renaming typedefs.
 typedef int SNIntegerType SWIFT_NAME(MyInt);
 
+// Renaming enumerations.
+SWIFT_ENUM(unsigned char, SNColorChoice) {
+  SNColorRed,
+  SNColorGreen,
+  SNColorBlue
+};
+
 // swift_private attribute
 void SNTransposeInPlace(struct SNSomeStruct *value) __attribute__((swift_private));
 

test/IDE/dump_swift_lookup_tables.swift

@@ -5,6 +5,7 @@
 // CHECK-NEXT:   Bar --> Bar
 // CHECK-NEXT:   MyInt --> MyInt
 // CHECK-NEXT:   Point --> Point
+// CHECK-NEXT:   SNColorChoice --> SNColorChoice
 // CHECK-NEXT:   SomeStruct --> SomeStruct
 // CHECK-NEXT:   __SNTransposeInPlace --> __SNTransposeInPlace
 // CHECK-NEXT:   makeSomeStruct --> makeSomeStruct(x:y:), makeSomeStruct(x:)
@@ -16,6 +17,8 @@
 // CHECK-NEXT:     TU: SNIntegerType
 // CHECK-NEXT:   Point:
 // CHECK-NEXT:     TU: SNPoint
+// CHECK-NEXT:   SNColorChoice:
+// CHECK-NEXT:     TU: SNColorChoice, SNColorChoice{{$}}
 // CHECK-NEXT:   SomeStruct:
 // CHECK-NEXT:     TU: SNSomeStruct
 // CHECK-NEXT:   __SNTransposeInPlace: