https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90046
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- Author: redi Date: Thu Apr 11 19:58:14 2019 New Revision: 270291 URL: https://gcc.gnu.org/viewcvs?rev=270291&root=gcc&view=rev Log: PR libstdc++/90046 fix build failure on epiphany-elf The epiphany-elf target aligns structs to 8 bytes, which causes the static_assert(alignof(_Chunk) == 1) to fail. Instead of requiring _Chunks to be positionable at any alignment, ensure new buffers are aligned to alignof(_Chunk). Because the buffer size is a power of two, we know that both the buffer size and sizeof(_Chunk) are multiples of alignof(_Chunk). So is p is aligned to alignof(_Chunk) then so is (p + size - sizeof(_Chunk)). So just ensure the new buffer is aligned to at least alignof(_Chunk), which should already be true because the caller requests at least alignof(max_align_t). PR libstdc++/90046 * src/c++17/memory_resource.cc (monotonic_buffer_resource::_Chunk::allocate): Increase alignment if needed to allow placing a _Chunk at the end of the buffer. (monotonic_buffer_resource::_M_new_buffer): Remove static_assert. Modified: trunk/libstdc++-v3/ChangeLog trunk/libstdc++-v3/src/c++17/memory_resource.cc
