[Bug gcov-profile/97834] gcov-instrumented binaries are very slow due to unbuffered IO

[nathan at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97834

--- Comment #5 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
you're looking in the wrong place.  see gcov_var and GCOV_BLOCK_SIZE.  it is
indeed 1k, but there;s some buffer doubling code in gcov_allocate that I don't
recall and am not sure why it's needed/