Improved semantic analysis and AST respresentation for function
templates.
For example, this now type-checks (but does not instantiate the body
of deref<int>):
template<typename T> T& deref(T* t) { return *t; }
void test(int *ip) {
int &ir = deref(ip);
}
Specific changes/additions:
* Template argument deduction from a call to a function template.
* Instantiation of a function template specializations (just the
declarations) from the template arguments deduced from a call.
* FunctionTemplateDecls are stored directly in declaration contexts
and found via name lookup (all forms), rather than finding the
FunctionDecl and then realizing it is a template. This is
responsible for most of the churn, since some of the core
declaration matching and lookup code assumes that all functions are
FunctionDecls.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@74213 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 71e88a9..e48ba15 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -269,6 +269,14 @@
// For function declarations, we keep track of redeclarations.
return FD->getPreviousDeclaration() == OldD;
+ // For function templates, the underlying function declarations are linked.
+ if (const FunctionTemplateDecl *FunctionTemplate
+ = dyn_cast<FunctionTemplateDecl>(this))
+ if (const FunctionTemplateDecl *OldFunctionTemplate
+ = dyn_cast<FunctionTemplateDecl>(OldD))
+ return FunctionTemplate->getTemplatedDecl()
+ ->declarationReplaces(OldFunctionTemplate->getTemplatedDecl());
+
// For method declarations, we keep track of redeclarations.
if (isa<ObjCMethodDecl>(this))
return false;