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| author | Patrick Palka <ppalka@redhat.com> | 2022-03-09 18:48:52 -0500 |
|---|---|---|
| committer | Patrick Palka <ppalka@redhat.com> | 2022-04-07 15:32:42 -0400 |
| commit | c859c99a85b8743b2c1edc097c6f6406de337f45 (patch) | |
| tree | e70081c8e23643fbb6c01cbf1e051c54b2895763 | |
| parent | 4e47b450b72f082de6fba7a060c3a751954e6c17 (diff) | |
| download | gcc-c859c99a85b8743b2c1edc097c6f6406de337f45.zip gcc-c859c99a85b8743b2c1edc097c6f6406de337f45.tar.gz gcc-c859c99a85b8743b2c1edc097c6f6406de337f45.tar.bz2 | |
libstdc++: Avoid implicit narrowing from uint128_t [PR104859]
We need to be explicit about narrowing conversions from uint128_t since,
on targets that lack __int128, this type is defined as an integer-class
type that is only _explicitly_ convertible to the builtin integer types.
This issue was latent until r12-7563-ge32869a17b788b made the frontend
correctly reject explicit conversion functions during (dependent)
copy-initialization.
PR libstdc++/104859
libstdc++-v3/ChangeLog:
* src/c++17/floating_to_chars.cc (__floating_to_chars_hex):
Be explicit when narrowing the shifted effective_mantissa,
since it may have an integer-class type.
(cherry picked from commit 65857caee8ccfac5007a9fd0e5f18cce5e5fe934)
| -rw-r--r-- | libstdc++-v3/src/c++17/floating_to_chars.cc | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/libstdc++-v3/src/c++17/floating_to_chars.cc b/libstdc++-v3/src/c++17/floating_to_chars.cc index 44f547a..2545022 100644 --- a/libstdc++-v3/src/c++17/floating_to_chars.cc +++ b/libstdc++-v3/src/c++17/floating_to_chars.cc @@ -799,14 +799,14 @@ template<typename T> char leading_hexit; if constexpr (has_implicit_leading_bit) { - const unsigned nibble = effective_mantissa >> rounded_mantissa_bits; + const auto 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 auto nibble = unsigned(effective_mantissa >> (rounded_mantissa_bits-4)); __glibcxx_assert(nibble < 16); leading_hexit = "0123456789abcdef"[nibble]; effective_mantissa &= ~(mantissa_t{0b1111} << (rounded_mantissa_bits-4)); @@ -847,7 +847,7 @@ template<typename T> while (effective_mantissa != 0) { nibble_offset -= 4; - const unsigned nibble = effective_mantissa >> nibble_offset; + const auto nibble = unsigned(effective_mantissa >> nibble_offset); __glibcxx_assert(nibble < 16); *first++ = "0123456789abcdef"[nibble]; ++written_hexits; |