Regular expression implementation that can be use for gcc4.8 [closed] - c++

Question

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 2 years ago.
Improve this question
Regular expressions will not work on gcc4.8 based on what I found out.
During cross compile I encountered run time errors with regards to regular expressions.
Do you know other ways how can i work with regex at gcc4.8?
I am thinking of creating my own but I wander if there is already available that can be use.

Answer 1

GCC 4.8 is really old (and no more maintained in 2020).
Consider updating it -in October 2020- to GCC 10 (whose source code you could compile) and read documentation about invoking GCC and using GDB. I suggest compiling with g++ -Wall -Wextra -g using a recent GCC.
Read at least the C++11 standard n3337 and a good C++ programming book and more about the #include <regex> standard header.
On Linux and POSIX systems, you could use regex(3). The source code is available, since open source (in e.g. the GNU libc or the musl-libc) and with permission you can adapt it to your working context.
You could also use Qt or POCO. Both have some regular expressions facilities and are open source. So you can study their source code implementation of regular expressions and their relation to push down automata. Read also about recursive descent parsers and consider using parser generators (if allowed) such as GNU bison, flex, or ANTLR. If performance is a major concern, consider using (with permission) code generating libraries like libgccjit, asmjit, GNU lightning, tinycc.
Of course, read the Dragon book. It explains the basic concepts for regular expressions. Read also recent papers to ACM SIGPLAN conferences.
If your management requires specifically GCC 4.8 (I would consider changing jobs with such a stupid requirement - since cross compiling GCC 10 is quite easy, and GCC improved a lot in five years), you should at least ask permission to compile some existing regular expression open source libraries (you'll find many of them on github or gitlab), or in boost.
Consider of course asking permission to use a recent Clang compiler (you could compile it from its source code, since it is open source), the Clang static analyzer, and perhaps Frama-C++, and to read this draft report. See also the CHARIOT and DECODER European projects.
PS. Cross-compiling GCC 10 takes one or two days (if you are a newbie). Writing your regular expression library could take you several weeks.