https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85270
Bug ID: 85270
Summary: Trivial assignment operator not considered such
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: hstong at ca dot ibm.com
Target Milestone: ---
Trivial copy assignment operator not considered such
GCC stops considering a trivial copy assignment operator to be trivial when a
non-trivial copy assignment operator is added to the class. Works with Clang;
fails with GCC.
### SOURCE (<stdin>):
struct Q {
Q &operator=(const Q &) = default;
// defaulted on first declaration, not user-provided; trivial
Q &operator=(Q &); // not a viable candidate at P1
};
static_assert(__is_trivially_assignable(Q &, const Q &), ""); // (P1)
// Assertion succeeds with Clang and ICC, but fails with GCC.
### COMPILER INVOCATION:
g++ -xc++ -std=c++2a -fsyntax-only -
### ACTUAL OUTPUT:
<stdin>:8:15: error: static assertion failed
### EXPECTED OUTPUT:
(Clean compile)
### COMPILER VERSION INFO (g++ -v):
Using built-in specs.
COLLECT_GCC=/opt/wandbox/gcc-head/bin/g++
COLLECT_LTO_WRAPPER=/opt/wandbox/gcc-head/libexec/gcc/x86_64-pc-linux-gnu/8.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../source/configure --prefix=/opt/wandbox/gcc-head
--enable-languages=c,c++ --disable-multilib --without-ppl --without-cloog-ppl
--enable-checking=release --disable-nls --enable-lto
LDFLAGS=-Wl,-rpath,/opt/wandbox/gcc-head/lib,-rpath,/opt/wandbox/gcc-head/lib64,-rpath,/opt/wandbox/gcc-head/lib32
Thread model: posix
gcc version 8.0.1 20180405 (experimental) (GCC)
