The logic in std::to_chars for extracting the high- and low-order parts
of a IBM long double value does the right thing on powerpc64le, but not
on powerpc64be. This patch makes the extraction endian-agnostic, which
fixes the execution FAIL of to_chars/long_double.cc on powerpc64be.
Tested on powerpc64le and powerpc64be. Does this look OK for trunk?
libstdc++-v3/ChangeLog:
PR libstdc++/98384
* src/c++17/floating_to_chars.cc (get_ieee_repr): Extract
the high- and low-order parts from an IBM long double value
in an endian-agnostic way.
---
libstdc++-v3/src/c++17/floating_to_chars.cc | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/libstdc++-v3/src/c++17/floating_to_chars.cc
b/libstdc++-v3/src/c++17/floating_to_chars.cc
index a50548acae7..4b2f85c1c1a 100644
--- a/libstdc++-v3/src/c++17/floating_to_chars.cc
+++ b/libstdc++-v3/src/c++17/floating_to_chars.cc
@@ -395,11 +395,11 @@ namespace
// of the high part, and we merge the mantissa of the high part with the
// mantissa (and the implicit leading bit) of the low part.
using uint_t = unsigned __int128;
- uint_t value_bits = 0;
- memcpy(&value_bits, &value, sizeof(value_bits));
+ uint64_t value_bits[2] = {};
+ memcpy(value_bits, &value, sizeof(value_bits));
- const uint64_t value_hi = value_bits;
- const uint64_t value_lo = value_bits >> 64;
+ const uint64_t value_hi = value_bits[0];
+ const uint64_t value_lo = value_bits[1];
uint64_t mantissa_hi = value_hi & ((1ull << 52) - 1);
unsigned exponent_hi = (value_hi >> 52) & ((1ull << 11) - 1);
--
2.30.1.559.g2283e0e9af
