1 files changed, 66 insertions, 0 deletions
diff --git a/clang/test/CodeGenCXX/weak-external.cpp b/clang/test/CodeGenCXX/weak-external.cpp
new file mode 100644
index 0000000..dad54f6
--- /dev/null
+++ b/clang/test/CodeGenCXX/weak-external.cpp
@@ -0,0 +1,66 @@
+// RUN: %clang -fexceptions %s -S -emit-llvm -o - | FileCheck %s
+// PR4262
+
+// CHECK-NOT: _ZNSs12_S_constructIPKcEEPcT_S3_RKSaIcESt20forward_iterator_tag
+
+// The "basic_string" extern template instantiation declaration is supposed to
+// suppress the implicit instantiation of non-inline member functions. Make sure
+// that we suppress the implicit instantiation of non-inline member functions
+// defined out-of-line. That we aren't instantiating the basic_string
+// constructor when we shouldn't be. Such an instantiation forces the implicit
+// instantiation of _S_construct<const char*>. Since _S_construct is a member
+// template, it's instantiation is *not* suppressed (despite being in
+// basic_string<char>), so we would emit it as a weak definition.
+
+#define _LIBCPP_EXCEPTION_ABI __attribute__ ((__visibility__("default")))
+#define _LIBCPP_INLINE_VISIBILITY __attribute__ ((__visibility__("hidden"), __always_inline__))
+#define _LIBCPP_VISIBLE __attribute__ ((__visibility__("default")))
+#if (__has_feature(cxx_noexcept))
+#  define _NOEXCEPT noexcept
+#  define _NOEXCEPT_(x) noexcept(x)
+#else
+#  define _NOEXCEPT throw()
+#  define _NOEXCEPT_(x)
+#endif
+
+namespace std  // purposefully not using versioning namespace
+{
+
+template<class charT> struct char_traits;
+template<class T>     class allocator;
+template <class _CharT,
+          class _Traits = char_traits<_CharT>,
+          class _Allocator = allocator<_CharT> >
+    class _LIBCPP_VISIBLE basic_string;
+typedef basic_string<char, char_traits<char>, allocator<char> > string;
+
+class _LIBCPP_EXCEPTION_ABI exception
+{
+public:
+    _LIBCPP_INLINE_VISIBILITY exception() _NOEXCEPT {}
+    virtual ~exception() _NOEXCEPT;
+    virtual const char* what() const _NOEXCEPT;
+};
+
+class _LIBCPP_EXCEPTION_ABI runtime_error
+    : public exception
+{
+private:
+    void* __imp_;
+public:
+    explicit runtime_error(const string&);
+    explicit runtime_error(const char*);
+
+    runtime_error(const runtime_error&) _NOEXCEPT;
+    runtime_error& operator=(const runtime_error&) _NOEXCEPT;
+
+    virtual ~runtime_error() _NOEXCEPT;
+
+    virtual const char* what() const _NOEXCEPT;
+};
+
+}
+
+void dummysymbol() {
+  throw(std::runtime_error("string"));
+}