https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85262
Bug ID: 85262
Summary: [6/7/8 Regression] Trouble with constructor and
-fpermissive
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code, rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: reichelt at gcc dot gnu.org
Target Milestone: ---
The following valid code snippet (compiled with "-fpermissive")
triggers an ICE on trunk:
================================
struct A {};
template<int> struct B : A
{
B()
{
A::A(A());
}
};
B<0> b;
================================
bug.cc: In constructor 'B<<anonymous> >::B()':
bug.cc:7:13: warning: cannot call constructor 'A::A' directly [-fpermissive]
A::A(A());
^
bug.cc:7:13: note: for a function-style cast, remove the redundant '::A'
bug.cc: In instantiation of 'B<<anonymous> >::B() [with int <anonymous> = 0]':
bug.cc:11:6: required from here
bug.cc:7:10: internal compiler error: in tsubst_copy, at cp/pt.c:15625
A::A(A());
^~~
0x63a8eb tsubst_copy
../../gcc/gcc/cp/pt.c:15625
0x96682b tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/gcc/cp/pt.c:18658
0x967f8c tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/gcc/cp/pt.c:18295
0x965a11 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/gcc/cp/pt.c:17543
0x971627 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:17099
0x97092e tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16300
0x96e71f tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16583
0x97005c tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16286
0x96e71f tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16583
0x96d8b8 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16271
0x96d8b8 instantiate_decl(tree_node*, bool, bool)
../../gcc/gcc/cp/pt.c:23682
0x99476b instantiate_pending_templates(int)
../../gcc/gcc/cp/pt.c:23798
0x8b8e3b c_parse_final_cleanups()
../../gcc/gcc/cp/decl2.c:4725
Please submit a full bug report, [etc.]
In GCC 6 and GCC 7 the code is wrongly rejected (when parsing the template,
the call to A::A is accepted with "-fpermissive", but at instantiation time
it is rejected) while a version without template compiles:
bug.cc: In constructor 'B<<anonymous> >::B()':
bu5.cc:7:13: warning: cannot call constructor 'A::A' directly [-fpermissive]
A::A(A());
^
bug.cc:7:13: note: for a function-style cast, remove the redundant '::A'
bug.cc: In instantiation of 'B<<anonymous> >::B() [with int <anonymous> = 0]':
bug.cc:11:6: required from here
bug.cc:7:9: error: cannot call constructor 'A::A' directly
A::A(A());
~~~~^~~~~
