Explicitly define ASTContext else the declaration will not export symbols.

src/CppParser/AST.cpp

@@ -447,6 +447,8 @@ ClassTemplate::FindPartialSpecialization(TemplateSpecializationType type)
     return 0;
 }
 
+ASTContext::ASTContext() {}
+
 TranslationUnit* ASTContext::FindOrCreateModule(std::string File)
 {
     // Clean up the file path.

src/CppParser/AST.h

@@ -702,6 +702,7 @@ struct CS_API NativeLibrary
 
 struct CS_API ASTContext
 {
+    ASTContext();
     TranslationUnit* FindOrCreateModule(std::string File);
     VECTOR(TranslationUnit*, TranslationUnits)
 };