[Bug c++/104859] [12 regression] liibg++ fails during bootstrap
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104859
Jakub Jelinek changed:
What|Removed |Added
CC||jakub at gcc dot gnu.org
--- Comment #7 from Jakub Jelinek ---
Oops, sorry, there is
template>>
constexpr explicit
operator T() const
{
static_assert(sizeof(T) <= sizeof(uint64_t));
return static_cast(lo);
}
but it is explicit so an explicit cast is needed.
[Bug c++/104859] [12 regression] liibg++ fails during bootstrap
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104859
--- Comment #6 from Jakub Jelinek ---
I'm more suprised that this ever worked.
For 32-bit libstdc++, there is no unsigned __int128 support, so it uses
uint128_t.h instead, but that class doesn't have conversion operator to
unsigned.
Wonder if
constexpr explicit
operator unsigned() const
{ return unsigned(lo); }
shouldn't be added to the header and then spots like
const unsigned nibble = effective_mantissa >> rounded_mantissa_bits;
be replaced with
const unsigned nibble = {effective_mantissa >> rounded_mantissa_bits};
[Bug c++/104859] [12 regression] liibg++ fails during bootstrap
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104859
Patrick Palka changed:
What|Removed |Added
Assignee|unassigned at gcc dot gnu.org |ppalka at gcc dot
gnu.org
Ever confirmed|0 |1
Status|UNCONFIRMED |ASSIGNED
Last reconfirmed||2022-03-09
--- Comment #5 from Patrick Palka ---
I think we just need to add some explicit casts:
diff --git a/libstdc++-v3/src/c++17/floating_to_chars.cc
b/libstdc++-v3/src/c++17/floating_to_chars.cc
index 5825e661bf4..0ccf2623511 100644
--- a/libstdc++-v3/src/c++17/floating_to_chars.cc
+++ b/libstdc++-v3/src/c++17/floating_to_chars.cc
@@ -801,14 +801,14 @@ template
char leading_hexit;
if constexpr (has_implicit_leading_bit)
{
- const unsigned nibble = effective_mantissa >> rounded_mantissa_bits;
+ const unsigned nibble = unsigned(effective_mantissa >>
rounded_mantissa_bits);
__glibcxx_assert(nibble <= 2);
leading_hexit = '0' + nibble;
effective_mantissa &= ~(mantissa_t{0b11} << rounded_mantissa_bits);
}
else
{
- const unsigned nibble = effective_mantissa >>
(rounded_mantissa_bits-4);
+ const unsigned nibble = unsigned(effective_mantissa >>
(rounded_mantissa_bits-4));
__glibcxx_assert(nibble < 16);
leading_hexit = "0123456789abcdef"[nibble];
effective_mantissa &= ~(mantissa_t{0b} <<
(rounded_mantissa_bits-4));
@@ -853,7 +853,7 @@ template
while (effective_mantissa != 0)
{
nibble_offset -= 4;
- const unsigned nibble = effective_mantissa >> nibble_offset;
+ const unsigned nibble = unsigned(effective_mantissa >>
nibble_offset);
__glibcxx_assert(nibble < 16);
*first++ = "0123456789abcdef"[nibble];
++written_hexits;
since on targets which lack __int128, effective_mantissa can be the
integer-class uint128_t, which unlike __int128 is only _explicitly_ convertible
to the builtin integer types. And r12-7563-ge32869a17b788b made us correctly
exclude explicit conversion operators during copy-initialization.
[Bug c++/104859] [12 regression] liibg++ fails during bootstrap
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104859 --- Comment #4 from Andrew Pinski --- (In reply to seurer from comment #3) > stage 1. It happens on a non-bootstrap, too. I was worried that it was causing wrong code in the front-end. Can you attach the preprocessed source for floating_to_chars.cc ?
[Bug c++/104859] [12 regression] liibg++ fails during bootstrap
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104859 --- Comment #3 from seurer at gcc dot gnu.org --- stage 1. It happens on a non-bootstrap, too.
[Bug c++/104859] [12 regression] liibg++ fails during bootstrap
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104859 Andrew Pinski changed: What|Removed |Added Target Milestone|--- |12.0 --- Comment #2 from Andrew Pinski --- What stage is the bootstrap at while the error happens?
