[gcc(refs/vendors/ARM/heads/arm-struct-reorg-wip)] c++: Fix stdcall attribute in template. [PR95222]

[Tamar Christina]

https://gcc.gnu.org/g:0c473d8f32510fcc96d584ee5099b856cfd3d8d6

commit 0c473d8f32510fcc96d584ee5099b856cfd3d8d6
Author: Jason Merrill <jason@redhat.com>
Date:   Mon May 25 19:04:05 2020 -0400

    c++: Fix stdcall attribute in template. [PR95222]
    
    Another case that breaks with my fix for PR90750: we shouldn't move type
    attributes in TYPENAME context either, as there's no decl for them to move
    to.
    
    gcc/cp/ChangeLog:
    
            PR c++/95222
            * decl.c (grokdeclarator): Don't shift attributes in TYPENAME
            context.
    
    gcc/testsuite/ChangeLog:
    
            PR c++/95222
            * g++.dg/ext/tmplattr10.C: New test.
    
    (cherry picked from commit 7e7d9fcff56385812764cba63e1ebf6f4c6c0320)

Diff:
---
 gcc/cp/decl.c                         |  2 +-
 gcc/testsuite/g++.dg/ext/tmplattr10.C | 52 +++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 232d7ed4a14..0d4af89e749 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -11941,7 +11941,7 @@ grokdeclarator (const cp_declarator *declarator,
 	  if (declarator->kind == cdk_array)
 	    attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
 	  tree late_attrs = NULL_TREE;
-	  if (decl_context != PARM)
+	  if (decl_context != PARM && decl_context != TYPENAME)
 	    /* Assume that any attributes that get applied late to
 	       templates will DTRT when applied to the declaration
 	       as a whole.  */
diff --git a/gcc/testsuite/g++.dg/ext/tmplattr10.C b/gcc/testsuite/g++.dg/ext/tmplattr10.C
new file mode 100644
index 00000000000..3fb8c21ccbe
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/tmplattr10.C
@@ -0,0 +1,52 @@
+// PR c++/95222
+// { dg-do compile { target { { i?86-*-* x86_64-*-* } && ia32 } } }
+
+#if defined(_MSC_VER)
+#define CC_FASTCALL __fastcall
+#define CC_STDCALL __stdcall
+#else
+#define CC_FASTCALL __attribute__((fastcall))
+#define CC_STDCALL __attribute__((stdcall))
+#endif
+
+template <typename FuncT>
+struct FuncResult;
+
+template <typename R, typename... Args>
+struct FuncResult<R(*)(Args...)>
+{
+    using type = R;
+};
+
+template <typename R, typename... Args>
+struct FuncResult<R(CC_FASTCALL*)(Args...)>
+{
+    using type = R;
+};
+
+template <typename R, typename... Args>
+struct FuncResult<R(CC_STDCALL*)(Args...)>
+{
+    using type = R;
+};
+
+template <typename FuncT>
+auto wrap(FuncT f) -> typename FuncResult<FuncT>::type
+{
+    return f(1, 2, 3);
+}
+
+int CC_FASTCALL func1(int x, int y, int z)
+{
+    return x + y + z;
+}
+
+int CC_STDCALL func2(int x, int y, int z)
+{
+    return x + y + z;
+}
+
+int main()
+{
+    return wrap(&func1) + wrap(&func2);
+}