Compiling C 11 with g

Question

I m trying to update my C   compiler to C  11  I have searched a bit and I have come to the conclusion that I have to use the flag -std c  0x or -std gnu  0x  but I don t know many things about flags  Can anyone help me   I m using Ubuntu 12 04    Here is the error that I get from the compiler when I attempt to use a library which is included in C  11  i e  array     include  lt array gt   include  lt iostream gt   int main         std  array lt int  3 gt  arr    2  3  5                  This file requires compiler and library support for the upcoming ISO C   standard  C  0x  This support is currently experimental  and must be enabled with the -std c  0x or -std gnu  0x compiler options

User · Answer

You can refer to following link for which features are supported in particular version of compiler. It has an exhaustive list of feature support in compiler. Looks GCC follows standard closely and implements before any other compiler.

Regarding your question you can compile using

g++ -std=c++11 for C++11
g++ -std=c++14 for C++14
g++ -std=c++17 for C++17
g++ -std=c++2a for C++20, although all features of C++20 are not yet supported refer this link for feature support list in GCC.

The list changes pretty fast, keep an eye on the list, if you are waiting for particular feature to be supported.

User · Answer

Flags  or compiler options  are nothing but ordinary command line arguments passed to the compiler executable   Assuming you are invoking g   from the command line  terminal      g   -std c  11 your file cpp -o your program  or    g   -std c  0x your file cpp -o your program  if the above doesn t work

User · Answer

If you want to keep the GNU compiler extensions  use -std gnu  0x rather than -std c  0x  Here s a quote from the man page      The compiler can accept several base standards  such as c89 or c  98    and GNU dialects of those standards  such as gnu89 or gnu  98  By   specifying a base standard  the compiler will accept all programs   following that standard and those using GNU extensions that do not   contradict it  For example  -std c89 turns off certain features of GCC   that are incompatible with ISO C90  such as the  asm  and  typeof    keywords  but not other GNU extensions that do not have a meaning in   ISO C90  such as omitting the middle term of a      expression  On the   other hand  by specifying a GNU dialect of a standard  all features   the compiler support are enabled  even when those features change the   meaning of the base standard and some strict-conforming programs may   be rejected   The particular standard is used by -pedantic to identify   which features are GNU extensions given that version of the standard    For example-std gnu89 -pedantic would warn about C   style      comments  while -std gnu99 -pedantic would not

User · Answer

You can check your g   by command   which g   g   --version   this will tell you which complier is currently it is pointing   To switch to g   4 7  assuming that you have installed it in your machine  run   sudo update-alternatives --config gcc  There are 2 choices for the alternative gcc  providing  usr bin gcc      Selection    Path              Priority   Status ------------------------------------------------------------   0             usr bin gcc-4 6   60        auto mode   1             usr bin gcc-4 6   60        manual mode   2             usr bin gcc-4 7   40        manual mode   Then select 2 as selection My machine already pointing to g   4 7 so the     Once you switch the complier then again run g   --version to check the switching has happened correctly   Now compile your program with   g   -std c  11 your file cpp -o main

User · Answer

Your Ubuntu definitely has a sufficiently recent version of g    The flag to use is -std c  0x

[c++] Compiling C++11 with g++

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