https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61720
Bug ID: 61720 Summary: std::regex_search matches incorrectly Product: gcc Version: 4.9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: husky.puppy at mail dot com Created attachment 33072 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33072&action=edit Preprocessed sourcce code When using std::regex_search to match the string R"("test\")" against the regular expression R"("([^"]|\\")*[^\\]")", it incorrectly finds a match. The std::regex_match on the other hand works as expected. Source: #include <regex> #include <iostream> int main() { std::string test = R"("test\")"; std::regex regex(R"("([^"]|\\")*[^\\]")"); std::smatch match; std::regex_search(test, match, regex); std::cout << "search: " << match.str() << std::endl; std::regex_match(test, match, regex); std::cout << "match: " << match.str() << std::endl; return 0; } Output: search: "test\" match: Command Line: g++ -std=c++11 -Wall -Werror test.cpp GCC Info: Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.9/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Debian 4.9.0-9' --with-bugurl=file:///usr/share/doc/gcc-4.9/README.Bugs --enable-languages=c,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.9 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.9 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --disable-libmudflap --disable-vtable-verify --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.9-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.9-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.9-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --with-arch-32=i586 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.9.0 (Debian 4.9.0-9) System Info: Linux server 3.14-1-amd64 #1 SMP Debian 3.14.9-1 (2014-06-30) x86_64 GNU/Linux