Cryptic gcc errors when building

[dasshiva]

This is an error which one might encounter when building gcc in the beginning

gcc: error: gengtype-lex.c: No such file or directory

As such this error makes no sense unless you really know that this is gcc telling you it could not generate its lexer.

This error is caused if your host system (the system you are compiling this on) is missing the flex program that provides the programs
flex and lex.

You may encounter other errors too if you use any other older version of gcc.
Although not every such error is unknown this link can guide you to fix some of the errors.

This issue is meant to be of help to anyone who may have forgotten to install the prerequisites to build gcc and/or has gotten stuck building gcc due to some error and can't make sense of the error message