Problems with Std::Stoi, Not Working on Mingw Gcc 4.7.2

Problems with std::stoi, not working on MinGW GCC 4.7.2

It seems your MinGW needs a patch: Enabling string conversion functions in MinGW

This patch enables the following list of C++11 functions and templates
in the std namespace:

stoi, stol, stoul, stoll, stof, stod, stold,
to_string, to_wstring

In above link, there is a .zip file, download it and

• Copy wchar.h and stdio.h from the include directory in the zip file
  to the following directory (overwrite): C:\mingw\include (replace
  C:\mingw\ with the appropriate directory)
• Copy os_defines.h to the following directory (overwrite):
  C:\mingw\lib\gcc\mingw32\4.7.0\include\c++\mingw32\bits (replace
  C:\mingw\ with the appropriate directory) (replace 4.7.0 with the
  correct version number)

std::stoi doesn't exist in g++ 4.6.1 on MinGW

This is a result of a non-standard declaration of vswprintf on Windows. The GNU Standard Library defines _GLIBCXX_HAVE_BROKEN_VSWPRINTF on this platform, which in turn disables the conversion functions you're attempting to use. You can read more about this issue and macro here: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37522.

If you're willing to modify the header files distributed with MinGW, you may be able to work around this by removing the !defined(_GLIBCXX_HAVE_BROKEN_VSWPRINTF) macro on line 2754 of .../lib/gcc/mingw32/4.6.1/include/c++/bits/basic_string.h, and adding it back around lines 2905 to 2965 (the lines that reference std::vswprintf). You won't be able to use the std::to_wstring functions, but many of the other conversion functions should be available.

MinGW g++ cannot find std::stof

Not sure about exact problem, but check mingw-w64 they have gcc 4.9.2 for now. It compiles your code just well. (But since the mingw-w64 project on sourceforge.net is moving to mingw-w64.org it's better to use mingw-w64.org)

Despite of it's name it provides compilers for both x86 and x64 targets.

^{Probably this should be a comment, not an answer.}

std::stod is not a member of std

std::stod is only available if you are at least using std=c++11 to compile. Therefore, when you compile, just add the flag -std=c++11 and you will be able to use stod

Error with stoi and debugged with gdb

Yeah, I think you're doing something pretty silly. You probably compiled the first code, which doesn't have the std::cout statement, and you probably executed the compilation steps without -std=c++11 which would result in std::stoi not being included beecause std::stoi is from C++11 and onward. The result is still the old executable which prints out nothing.

Recompile using -std=c++11 and make sure that you saved your file correctly. Your code clearly works.

Note: the vanilla port of GCC of MinGW on Windows is flawed and has a few bugs related to C++11 and onwards; using MinGW-w64, if you ever decide to compile on Windows, can help the problem.

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