From e035b27686940997d4a28fa97f3c0edd107faea4 Mon Sep 17 00:00:00 2001
From: Dimitar Dobrev <dpldobrev@protonmail.com>
Date: Fri, 21 Dec 2018 14:35:12 +0200
Subject: [PATCH] Fixed a crash when parsing type aliases.

This was caused by a change in behaviour in Clang - https://github.com/llvm-mirror/clang/commit/a8770a7e8e8797a860773c2e0959274b1db4fc7a (SVN revision 346146).

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>
---
 src/CppParser/Parser.cpp | 8 ++++----
 tests/Common/Common.h    | 9 +++++++++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/CppParser/Parser.cpp b/src/CppParser/Parser.cpp
index e84fb8af..9792e986 100644
--- a/src/CppParser/Parser.cpp
+++ b/src/CppParser/Parser.cpp
@@ -2475,7 +2475,7 @@ Type* Parser::WalkType(clang::QualType QualType, const clang::TypeLoc* TL,
         TST->_template = static_cast<Template*>(WalkDeclaration(
             Name.getAsTemplateDecl()));
         if (TS->isSugared())
-            TST->desugared = GetQualifiedType(TS->desugar(), TL);
+            TST->desugared = GetQualifiedType(TS->getCanonicalTypeInternal(), TL);
 
         TypeLoc UTL, ETL, ITL;
 
@@ -2518,7 +2518,7 @@ Type* Parser::WalkType(clang::QualType QualType, const clang::TypeLoc* TL,
         auto TST = new DependentTemplateSpecializationType();
 
         if (TS->isSugared())
-            TST->desugared = GetQualifiedType(TS->desugar(), TL);
+            TST->desugared = GetQualifiedType(TS->getCanonicalTypeInternal(), TL);
 
         TypeLoc UTL, ETL, ITL;
 
@@ -2706,7 +2706,7 @@ Type* Parser::WalkType(clang::QualType QualType, const clang::TypeLoc* TL,
 
         auto UTT = new UnaryTransformType();
         auto Loc = TL->getAs<UnaryTransformTypeLoc>().getUnderlyingTInfo()->getTypeLoc();
-        UTT->desugared = GetQualifiedType(UT->isSugared() ? UT->desugar() : UT->getBaseType(), &Loc);
+        UTT->desugared = GetQualifiedType(UT->isSugared() ? UT->getCanonicalTypeInternal() : UT->getBaseType(), &Loc);
         UTT->baseType = GetQualifiedType(UT->getBaseType(), &Loc);
 
         Ty = UTT;
@@ -2733,7 +2733,7 @@ Type* Parser::WalkType(clang::QualType QualType, const clang::TypeLoc* TL,
     {
         auto AT = Type->getAs<clang::AutoType>();
         if (AT->isSugared())
-            Ty = WalkType(AT->desugar());
+            Ty = WalkType(AT->getCanonicalTypeInternal());
         else
             return nullptr;
         break;
diff --git a/tests/Common/Common.h b/tests/Common/Common.h
index 8e32acd0..0b6117dd 100644
--- a/tests/Common/Common.h
+++ b/tests/Common/Common.h
@@ -1457,3 +1457,12 @@ class MyIntList : public MyList<int>
 };
 
 void MyFunc(MyList<void *> *list);
+
+template<class T> using InvokeGenSeq = typename T::Type;
+
+template<int N> struct DerivedTypeAlias;
+template<int N> using TypeAlias = InvokeGenSeq<DerivedTypeAlias<N>>;
+
+template<int N>
+struct DerivedTypeAlias : TypeAlias<N / 2> {};
+