regex - C++ (C++11) regular expressions differences on OS X and Linux -

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• is gcc 4.8 or earlier buggy regular expressions? 3 answers

i'm trying code work on both os x , linux same. code below compiled clang++ --std=c++11 regextest.cpp

#include <regex> #include <iostream> int main() {     std::string str = "/api/asd/";     std::string pattern = "/api/(.*)/";     std::cout << "starting matching" << std::endl;     std::smatch matches;     if (std::regex_match(str, matches, std::regex(pattern, std::regex::egrep)))     {         std::cout << "found match!" << std::endl;         std::cout << "all matches: ";         (auto& : matches)             std::cout << << ", ";         std::cout << std::endl;     }     return 0; } 

on os x, result of running code is:

starting matching found match! matches: /api/asd/, asd, 

on linux, on other hand (gentoo, libstdc++ 3.3)

starting matching found match! matches: /api/asd/, /asd/, // 

how match /api/ on linux? why?

additionally, trying use pattern /api/([^/]) fails in linux , matches nothing works in os x.

i've tried many combinations of match types, (basic, extended, grep, egrep, awk) escaped , unescaped ( , ) (depending on match type) , nothing produces expected results on linux.

as suggested comments, issue solved upgrading gcc 4.9. (~amd64 flag required on gentoo).