Make command on Linux(Redhat) yieldspthreads_undefined error. Also gcc compatiblity note

[MdotO]

Hi.
This issue is half FYI and half confirmation of the solution.
Just wanted to point out that I when I ran the mkae file in my rhel 8 enterprise linux with gcc 12, the following error came up :
undefined reference to pthread_create
I solved it by adjusting Makefile line to
CFLAGS := -O3 -fPIC -Wall -Werror -Weffc++ -std=c++20 -pedantic -pthread ( after seeing that these flags were used for .c to .o compilation only)
The other fix would be add #include <pthreads.h> to corresonding c files
Please do let me know if this is indeed the right thing to do and also confused as to why this issue wasnt raised before coz I am very sure it would be a common error unless ofcourse I am doing something wrong
Note: the current c++2a standard (which provides definitions for erase_if among others) is only supported by gcc 9 + versions)

[camilleg]

The last line of this issue, "c++2a is only supported by gcc 9+", is known.
It's already mentioned in the readme's section "Ubuntu 18 and older."