fix PR7519: after thrashing around and remembering how all this stuff

works, the fix is quite simple: just make sure to call ConvertTypeRecursive
when the function type being lowered is in the midst of ConvertType.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@107173 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 68 insertions, 26 deletions

diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index bfc22d1bc7..cbcd3d1233 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -61,28 +61,31 @@ static CanQualType GetReturnType(QualType RetTy) {
 }
 
 const CGFunctionInfo &
-CodeGenTypes::getFunctionInfo(CanQual<FunctionNoProtoType> FTNP) {
+CodeGenTypes::getFunctionInfo(CanQual<FunctionNoProtoType> FTNP,
+                              bool IsRecursive) {
   return getFunctionInfo(FTNP->getResultType().getUnqualifiedType(),
                          llvm::SmallVector<CanQualType, 16>(),
-                         FTNP->getExtInfo());
+                         FTNP->getExtInfo(), IsRecursive);
 }
 
 /// \param Args - contains any initial parameters besides those
 ///   in the formal type
 static const CGFunctionInfo &getFunctionInfo(CodeGenTypes &CGT,
                                   llvm::SmallVectorImpl<CanQualType> &ArgTys,
-                                             CanQual<FunctionProtoType> FTP) {
+                                             CanQual<FunctionProtoType> FTP,
+                                             bool IsRecursive = false) {
   // FIXME: Kill copy.
   for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i)
     ArgTys.push_back(FTP->getArgType(i));
   CanQualType ResTy = FTP->getResultType().getUnqualifiedType();
-  return CGT.getFunctionInfo(ResTy, ArgTys, FTP->getExtInfo());
+  return CGT.getFunctionInfo(ResTy, ArgTys, FTP->getExtInfo(), IsRecursive);
 }
 
 const CGFunctionInfo &
-CodeGenTypes::getFunctionInfo(CanQual<FunctionProtoType> FTP) {
+CodeGenTypes::getFunctionInfo(CanQual<FunctionProtoType> FTP,
+                              bool IsRecursive) {
   llvm::SmallVector<CanQualType, 16> ArgTys;
-  return ::getFunctionInfo(*this, ArgTys, FTP);
+  return ::getFunctionInfo(*this, ArgTys, FTP, IsRecursive);
 }
 
 static CallingConv getCallingConventionForDecl(const Decl *D) {
@@ -215,7 +218,8 @@ const CGFunctionInfo &CodeGenTypes::getFunctionInfo(QualType ResTy,
 
 const CGFunctionInfo &CodeGenTypes::getFunctionInfo(CanQualType ResTy,
                            const llvm::SmallVectorImpl<CanQualType> &ArgTys,
-                                            const FunctionType::ExtInfo &Info) {
+                                            const FunctionType::ExtInfo &Info,
+                                                    bool IsRecursive) {
 #ifndef NDEBUG
   for (llvm::SmallVectorImpl<CanQualType>::const_iterator
          I = ArgTys.begin(), E = ArgTys.end(); I != E; ++I)
@@ -243,8 +247,17 @@ const CGFunctionInfo &CodeGenTypes::getFunctionInfo(CanQualType ResTy,
   // various situations, pass it in.
   llvm::SmallVector<const llvm::Type *, 8> PreferredArgTypes;
   for (llvm::SmallVectorImpl<CanQualType>::const_iterator
-       I = ArgTys.begin(), E = ArgTys.end(); I != E; ++I)
-    PreferredArgTypes.push_back(ConvertType(*I));
+       I = ArgTys.begin(), E = ArgTys.end(); I != E; ++I) {
+    // If this is being called from the guts of the ConvertType loop, make sure
+    // to call ConvertTypeRecursive so we don't get into issues with cyclic
+    // pointer type structures.
+    const llvm::Type *ArgType;
+    if (IsRecursive)
+      ArgType = ConvertTypeRecursive(*I);
+    else 
+      ArgType = ConvertType(*I);
+    PreferredArgTypes.push_back(ArgType);
+  }
 
   // Compute ABI information.
   getABIInfo().computeInfo(*FI, getContext(), TheModule.getContext(),
diff --git a/lib/CodeGen/CodeGenTypes.cpp b/lib/CodeGen/CodeGenTypes.cpp
index cf23c07394..6ff394e03c 100644
--- a/lib/CodeGen/CodeGenTypes.cpp
+++ b/lib/CodeGen/CodeGenTypes.cpp
@@ -46,7 +46,7 @@ CodeGenTypes::~CodeGenTypes() {
 const llvm::Type *CodeGenTypes::ConvertType(QualType T) {
   llvm::PATypeHolder Result = ConvertTypeRecursive(T);
 
-  // Any pointers that were converted defered evaluation of their pointee type,
+  // Any pointers that were converted deferred evaluation of their pointee type,
   // creating an opaque type instead.  This is in order to avoid problems with
   // circular types.  Loop through all these defered pointees, if any, and
   // resolve them now.
@@ -284,7 +284,8 @@ const llvm::Type *CodeGenTypes::ConvertNewType(QualType T) {
     assert(A.getIndexTypeCVRQualifiers() == 0 &&
            "FIXME: We only handle trivial array types so far!");
     // int X[] -> [0 x int]
-    return llvm::ArrayType::get(ConvertTypeForMemRecursive(A.getElementType()), 0);
+    return llvm::ArrayType::get(ConvertTypeForMemRecursive(A.getElementType()),
+                                0);
   }
   case Type::ConstantArray: {
     const ConstantArrayType &A = cast<ConstantArrayType>(Ty);
@@ -299,7 +300,11 @@ const llvm::Type *CodeGenTypes::ConvertNewType(QualType T) {
   }
   case Type::FunctionNoProto:
   case Type::FunctionProto: {
-    // First, check whether we can build the full function type.
+    // First, check whether we can build the full function type.  If the
+    // function type depends on an incomplete type (e.g. a struct or enum), we
+    // cannot lower the function type.  Instead, turn it into an Opaque pointer
+    // and have UpdateCompletedType revisit the function type when/if the opaque
+    // argument type is defined.
     if (const TagType *TT = VerifyFuncTypeComplete(&Ty)) {
       // This function's type depends on an incomplete tag type; make sure
       // we have an opaque type corresponding to the tag type.
@@ -309,17 +314,25 @@ const llvm::Type *CodeGenTypes::ConvertNewType(QualType T) {
       FunctionTypes.insert(std::make_pair(&Ty, ResultType));
       return ResultType;
     }
+    
     // The function type can be built; call the appropriate routines to
     // build it.
-    if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(&Ty))
-      return GetFunctionType(getFunctionInfo(
-                CanQual<FunctionProtoType>::CreateUnsafe(QualType(FPT,0))),
-                             FPT->isVariadic());
-
-    const FunctionNoProtoType *FNPT = cast<FunctionNoProtoType>(&Ty);
-    return GetFunctionType(getFunctionInfo(
-                CanQual<FunctionNoProtoType>::CreateUnsafe(QualType(FNPT,0))),
-                           true);
+    const CGFunctionInfo *FI;
+    bool isVariadic;
+    if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(&Ty)) {
+      FI = &getFunctionInfo(
+                   CanQual<FunctionProtoType>::CreateUnsafe(QualType(FPT, 0)),
+                            true /*Recursive*/);
+      isVariadic = FPT->isVariadic();
+    } else {
+      const FunctionNoProtoType *FNPT = cast<FunctionNoProtoType>(&Ty);
+      FI = &getFunctionInfo(
+                CanQual<FunctionNoProtoType>::CreateUnsafe(QualType(FNPT, 0)),
+                            true /*Recursive*/);
+      isVariadic = true;
+    }
+
+    return GetFunctionType(*FI, isVariadic);
   }
 
   case Type::ObjCObject:
diff --git a/lib/CodeGen/CodeGenTypes.h b/lib/CodeGen/CodeGenTypes.h
index 674fe8f8b4..ff2c32904f 100644
--- a/lib/CodeGen/CodeGenTypes.h
+++ b/lib/CodeGen/CodeGenTypes.h
@@ -154,8 +154,11 @@ public:
     return getFunctionInfo(Ty->getResultType(), Args,
                            Ty->getExtInfo());
   }
-  const CGFunctionInfo &getFunctionInfo(CanQual<FunctionProtoType> Ty);
-  const CGFunctionInfo &getFunctionInfo(CanQual<FunctionNoProtoType> Ty);
+
+  const CGFunctionInfo &getFunctionInfo(CanQual<FunctionProtoType> Ty,
+                                        bool IsRecursive = false);
+  const CGFunctionInfo &getFunctionInfo(CanQual<FunctionNoProtoType> Ty,
+                                        bool IsRecursive = false);
 
   // getFunctionInfo - Get the function info for a member function.
   const CGFunctionInfo &getFunctionInfo(const CXXRecordDecl *RD,
@@ -176,7 +179,8 @@ public:
   /// \param ArgTys - must all actually be canonical as params
   const CGFunctionInfo &getFunctionInfo(CanQualType RetTy,
                                const llvm::SmallVectorImpl<CanQualType> &ArgTys,
-                                        const FunctionType::ExtInfo &Info);
+                                        const FunctionType::ExtInfo &Info,
+                                        bool IsRecursive = false);
 
   /// \brief Compute a new LLVM record layout object for the given record.
   CGRecordLayout *ComputeRecordLayout(const RecordDecl *D);
diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp
index 2ba19f1096..c65f203715 100644
--- a/lib/CodeGen/TargetInfo.cpp
+++ b/lib/CodeGen/TargetInfo.cpp
@@ -830,8 +830,7 @@ X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
   return SSE;
 }
 
-void X86_64ABIInfo::classify(QualType Ty,
-                             uint64_t OffsetBase,
+void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
                              Class &Lo, Class &Hi) const {
   // FIXME: This code can be simplified by introducing a simple value class for
   // Class pairs with appropriate constructor methods for the various
diff --git a/test/CodeGen/decl.c b/test/CodeGen/decl.c
index 7ffb7006b0..dcf120fd88 100644
--- a/test/CodeGen/decl.c
+++ b/test/CodeGen/decl.c
@@ -89,3 +89,16 @@ struct test7s { int a; int b; } test7[] = {
 struct test8s { int f0; char f1; } test8g = {};
 
 
+// PR7519
+
+struct S {
+  void (*x) (struct S *);
+};
+
+extern struct S *global_dc;
+void cp_diagnostic_starter(struct S *);
+
+void init_error(void) {
+  global_dc->x = cp_diagnostic_starter;
+}
+