https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124463
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I've tried to check if it is the compiler or libstdc++ header size, when
preprocessing with g++ 14.1 (I was lazy, so on godbolt) I get the same speed
when compiled by both GCC 14 (current) and GCC 15 (current). g++ here is my
system 15.2.1:
/usr/src/gcc-14/obj16/gcc/cc1plus -quiet -O3 -std=gnu++17 -o pr124463.s
pr124463.ii; g++ -o pr124463{,.s}; ./pr124463
Streaming 1176 MB total...
std::deque<unsigned char>: 145 ms
std::deque<unsigned char>: 145 ms
std::deque<unsigned char>: 145 ms
/usr/src/gcc-15/obj08/gcc/cc1plus -quiet -O3 -std=gnu++17 -o pr124463.s
pr124463.ii; g++ -o pr124463{,.s}; ./pr124463
Streaming 1176 MB total...
std::deque<unsigned char>: 144 ms
std::deque<unsigned char>: 143 ms
std::deque<unsigned char>: 143 ms
g++ -O3 -std=gnu++17 -o pr124463{,.C}; ./pr124463
Streaming 1176 MB total...
std::deque<unsigned char>: 595 ms
std::deque<unsigned char>: 594 ms
std::deque<unsigned char>: 594 ms
