[MS] Instantiate default args during instantiation of exported default ctors

Summary:
Replace some old code that probably pre-dated the change to delay
emission of dllexported code until after the closing brace of the
outermost record type. Only uninstantiated default argument expressions
need to be handled now. It is enough to instantiate default argument
expressions when instantiating dllexported default ctors. This also
fixes some double-diagnostic issues in this area.

Fixes PR31500

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D28274

llvm-svn: 291045

1 files changed, 21 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/dllexport.cpp b/clang/test/SemaCXX/dllexport.cpp
index b4850fc03d9..a3fed70ec95 100644
--- a/clang/test/SemaCXX/dllexport.cpp
+++ b/clang/test/SemaCXX/dllexport.cpp
@@ -741,6 +741,27 @@ struct __declspec(dllexport) ClassWithMultipleDefaultCtors {
   ClassWithMultipleDefaultCtors(int = 40) {} // expected-error{{'__declspec(dllexport)' cannot be applied to more than one default constructor}}
   ClassWithMultipleDefaultCtors(int = 30, ...) {} // expected-note{{declared here}}
 };
+template <typename T>
+struct ClassTemplateWithMultipleDefaultCtors {
+  __declspec(dllexport) ClassTemplateWithMultipleDefaultCtors(int = 40) {}      // expected-error{{'__declspec(dllexport)' cannot be applied to more than one default constructor}}
+  __declspec(dllexport) ClassTemplateWithMultipleDefaultCtors(int = 30, ...) {} // expected-note{{declared here}}
+};
+
+template <typename T> struct HasDefaults {
+  HasDefaults(int x = sizeof(T)) {} // expected-error {{invalid application of 'sizeof'}}
+};
+template struct __declspec(dllexport) HasDefaults<char>;
+
+template struct
+__declspec(dllexport) // expected-note {{in instantiation of default function argument expression for 'HasDefaults<void>' required here}}
+HasDefaults<void>; // expected-note {{in instantiation of member function 'HasDefaults<void>::HasDefaults' requested here}}
+
+template <typename T> struct HasDefaults2 {
+  __declspec(dllexport) // expected-note {{in instantiation of default function argument expression for 'HasDefaults2<void>' required here}}
+  HasDefaults2(int x = sizeof(T)) {} // expected-error {{invalid application of 'sizeof'}}
+};
+template struct HasDefaults2<void>; // expected-note {{in instantiation of member function 'HasDefaults2<void>::HasDefaults2' requested here}}
+
 #endif
 
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