As I mentioned in the PR, the problem here is that we're replacing a
constructor with a dispatcher function which doesn't look much like a
constructor. This patch adjusts make_dispatcher_decl to make it look
more like the functions it dispatches to, but other things are certain
to break for similar reasons down the road. A proper solution should
be more transparent, like thunks.
Tested x86_64-pc-linux-gnu. Does this seem worth applying to fix the
regression?
commit d3b4453834bb2e3cc1c875e76fe593c16f263f77
Author: Jason Merrill <ja...@redhat.com>
Date: Fri Feb 16 16:53:47 2018 -0500
PR c++/83911 - ICE with multiversioned constructor.
gcc/
* attribs.c (make_dispatcher_decl): Copy METHOD_TYPE,
DECL_CXX_{CON,DE}STRUCTOR_P.
gcc/cp/
* cp-tree.h (DECL_CONSTRUCTOR_P): Use DECL_CXX_CONSTRUCTOR_P.
(DECL_DESTRUCTOR_P): Use DECL_CXX_DESTRUCTOR_P.
* mangle.c (write_unqualified_name): Check IDENTIFIER_[CD]TOR_P.
diff --git a/gcc/attribs.c b/gcc/attribs.c
index bfadf124dcb..2e9e69904f0 100644
--- a/gcc/attribs.c
+++ b/gcc/attribs.c
@@ -1063,9 +1063,14 @@ make_dispatcher_decl (const tree decl)
func_name = xstrdup (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
fn_type = TREE_TYPE (decl);
- func_type = build_function_type (TREE_TYPE (fn_type),
- TYPE_ARG_TYPES (fn_type));
-
+ if (TREE_CODE (fn_type) == METHOD_TYPE)
+ func_type = build_method_type_directly (TYPE_METHOD_BASETYPE (fn_type),
+ TREE_TYPE (fn_type),
+ TYPE_ARG_TYPES (fn_type));
+ else
+ func_type = build_function_type (TREE_TYPE (fn_type),
+ TYPE_ARG_TYPES (fn_type));
+
func_decl = build_fn_decl (func_name, func_type);
XDELETEVEC (func_name);
TREE_USED (func_decl) = 1;
@@ -1078,6 +1083,9 @@ make_dispatcher_decl (const tree decl)
/* This will be of type IFUNCs have to be externally visible. */
TREE_PUBLIC (func_decl) = 1;
+ DECL_CXX_CONSTRUCTOR_P (func_decl) = DECL_CXX_CONSTRUCTOR_P (decl);
+ DECL_CXX_DESTRUCTOR_P (func_decl) = DECL_CXX_DESTRUCTOR_P (decl);
+
return func_decl;
}
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 17d8c6d2650..268be0fd543 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -2695,7 +2695,7 @@ struct GTY(()) lang_decl {
/* For FUNCTION_DECLs and TEMPLATE_DECLs: nonzero means that this function
is a constructor. */
#define DECL_CONSTRUCTOR_P(NODE) \
- IDENTIFIER_CTOR_P (DECL_NAME (NODE))
+ DECL_CXX_CONSTRUCTOR_P (STRIP_TEMPLATE (NODE))
/* Nonzero if NODE (a FUNCTION_DECL) is a constructor for a complete
object. */
@@ -2724,7 +2724,7 @@ struct GTY(()) lang_decl {
/* Nonzero if NODE (a FUNCTION_DECL or TEMPLATE_DECL)
is a destructor. */
#define DECL_DESTRUCTOR_P(NODE) \
- IDENTIFIER_DTOR_P (DECL_NAME (NODE))
+ DECL_CXX_DESTRUCTOR_P (STRIP_TEMPLATE (NODE))
/* Nonzero if NODE (a FUNCTION_DECL) is a destructor, but not the
specialized in-charge constructor, in-charge deleting constructor,
diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c
index 94c4bed2848..ecd4eb066d4 100644
--- a/gcc/cp/mangle.c
+++ b/gcc/cp/mangle.c
@@ -1351,9 +1351,9 @@ write_unqualified_name (tree decl)
else if (DECL_DECLARES_FUNCTION_P (decl))
{
found = true;
- if (DECL_CONSTRUCTOR_P (decl))
+ if (IDENTIFIER_CTOR_P (DECL_NAME (decl)))
write_special_name_constructor (decl);
- else if (DECL_DESTRUCTOR_P (decl))
+ else if (IDENTIFIER_DTOR_P (DECL_NAME (decl)))
write_special_name_destructor (decl);
else if (DECL_CONV_FN_P (decl))
{
diff --git a/gcc/testsuite/g++.dg/ext/mv27.C b/gcc/testsuite/g++.dg/ext/mv27.C
new file mode 100644
index 00000000000..443a54be765
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/mv27.C
@@ -0,0 +1,18 @@
+// PR c++/83911
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-require-ifunc "" }
+
+class SimdFloat
+{
+public:
+ __attribute__ ((target ("default")))
+ SimdFloat(float x) {}
+
+ __attribute__ ((target ("avx2")))
+ SimdFloat(float x) {}
+};
+
+SimdFloat foo()
+{
+ return 1;
+}
