I'm still having an issue with the bug from g++ 4.6.1 however the solution provided doesn't seem relevant to g++ 5.3.0. Is there any other workaround besides installing mingw-w64?
My build command is:
g++ main1.cpp main2.cpp -g -std=gnu++11 -o program.exe
Related
I need to use C++98 for university programs, however even when passing the -std=c++98 flag to clang++ or to g++ it still seems to compile with c++11 and does not give errors if I use c++11 features. Here is a simple example:
#include <string>
#include <sstream>
using namespace std;
int main()
{
int i;
string number = "12";
i = stoi(number);
}
My makefile:
all:
clang++ -std=c++98 -c *.cpp
clang++ -o main *.o
clean:
rm -f *.o main
run: clean all
./main
Then I run the command make from Terminal (I tried using clang++ instead of g++ but it yields the same result) and receive the following output:
➜ cppversion make
g++ -std=c++98 -c *.cpp
g++ -o main *.o
➜ cppversion make
clang++ -std=c++98 -c *.cpp
clang++ -o main *.o
➜ cppversion
I believe this code should not have compiled if the -std=c++98 flag was working. How do I force code to compile with c++98?
Here is the version of clang:
Apple clang version 12.0.5 (clang-1205.0.22.11)
Target: x86_64-apple-darwin20.2.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin\
Here is the version of g++:
Configured with: --prefix=/Library/Developer/CommandLineTools/usr --with-gxx-include-dir=/Library/Developer/CommandLineTools/SDKs/MacOSX11.1.sdk/usr/include/c++/4.2.1
Apple clang version 12.0.5 (clang-1205.0.22.11)
Target: x86_64-apple-darwin20.2.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin
I have also tried adding the flag -pedantic but it does not fix the problem.
Using the flag -stdlib=libc++ yields the following:
➜ cppversion make
clang++ -stdlib=libstdc++ -std=c++98 -c *.cpp
clang: warning: include path for libstdc++ headers not found; pass '-stdlib=libc++' on the command line to use the libc++ standard library instead [-Wstdlibcxx-not-found]
main.cpp:1:10: fatal error: 'string' file not found
#include <string>
^~~~~~~~
1 error generated.
make: *** [all] Error 1
If I change it to just -stdlib=libc++ then it still compiles:
➜ cppversion make
clang++ -stdlib=libc++ -std=c++98 -c *.cpp
clang++ -o main *.o
➜ cppversion
I found an easy solution: Use homebrew to install gcc and use g++-11 to compile.
Try using -std=c++98 -pedantic.
This should strictly enforce the specific standard.
Disclaimer: This is partly guesswork since I don't have a Mac
From my understanding, clang++ is the default compiler on Mac and I would therefore not be surprised if even g++ uses LLVM:s libc++ and headers by default. std::stoi is unconditionaly declared in the libc++ headers.
If you instead useg++:s libstdc++ toolchain, you will probably get the error you want:
clang++ -stdlib=libstdc++ -std=c++98 -o main main.cpp
I found an easy solution: Use homebrew to install gcc and use g++-11 to compile.
I can build c++ projects without c++ modules with build2, but when i try to configure and use build2 with c++ modules, I have "compiler does not support modules" error.
I'm sure my compiler is capable of building modules, because I can manually build using these commands:
clang++ --std=c++17 -fmodules-ts --precompile foo.cppm -o foo.pcm
clang++ --std=c++17 -fmodules-ts --precompile foo2.cppm -o foo2.pcm
clang++ --std=c++17 -fmodules-ts -c foo.pcm -o foo.o
clang++ --std=c++17 -fmodules-ts -c foo2.pcm -o foo2.o
clang++ --std=c++17 -fmodules-ts -fprebuilt-module-path=. foo.o foo2.o bar.cpp
Version of my clang is 7.0.0:
$ clang++ --version
clang version 7.0.0- (trunk)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
To enable modules support in build2 I added following lines to root buildfile:
cxx.std = experimental
using cxx
assert $cxx.features.modules 'compiler does not support modules'
mxx{*}: extension = mxx
cxx{*}: extension = cxx
What can be wrong? It's my first time with build2, so I can be missing something very simple.
Managed it to work.
As I understand the problem was that I changed buildfile, but should use build/root.build instead.
I'm trying to configure eclipise kepler to use c++ 11.
I appended -std=c++11 to:
Properties > c/c++ build > settings > GCC c++ complier > Miscellaneous>other flags
But when I compile the project it says:
compilation terminated. /bin/sh: 1: -std=c++11: not found
I'm using gcc on ubuntu,
any ideas?
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++ -Wall -g -std=c++11 your_file.cpp -o your_program
or
$ g++ -Wall -g -std=c++0x your_file.cpp -o your_program
if the above doesn't work.
So in your case if -std=c++11 does not work, try -std=c++0x
Another source for this error could be an old compiler version.
Type gcc --version into the terminal and check the version. Here is a quick overview which version is capable of c++11:
C++11 Support in GCC
GCC 4.8.1 was the first feature-complete implementation of the 2011
C++ standard, previously known as C++0x.
This mode can be selected with the -std=c++11 command-line flag, or
-std=gnu++11 to enable GNU extensions as well.
Link: https://gcc.gnu.org/projects/cxx-status.html
I'm taking part in a programming contest and the requirement is that code will be compiled using following command:
g++ -std=c++11 -O2 -o a.out orienteering.cpp
How do I check if my code works for this command? (I use DevC++ for coding and it has automatic compilation).
Also compiler should be GCC 4.8.2 or later. What does this mean? Is my older GCC version (4.7.2) not suitable?
You check your code by placing it in a file named orienteering.cpp, and running this command in the same directory:
g++ -std=c++11 -O2 -o a.out orienteering.cpp
If the compiler spits out any messages at all then you have a problem. If the compiler is silent and creates a file named a.out, then all is well.
GCC 4.7.2 does not meet the criteria "GCC 4.8.2 or later".
I have a warning involving /usr/local/lib/gcc/x86_64-apple-darwin10.8.0/4.6.4/libgcc.a. I was trying to compile a C++ project using a Makefile, which shows the following:
executeit: bplustree.o nonleafnode.o leafnode.o
g++ -o executeit bplustree.o nonleafnode.o leafnode.o
bplustree.o: bplustree.cpp
g++ -g -c bplustree.cpp
nonleafnode.o: nonleafnode.h nonleafnode.cpp
g++ -g -c nonleafnode.h nonleafnode.cpp
leafnode.o: leafnode.h leafnode.cpp
g++ -g -c leafnode.h leafnode.cpp
clean:
rm executeit bplustree.o nonleafnode.o leafnode.o
When I invoke "make", I get the following output in Terminal:
g++ -g -c bplustree.cpp
g++ -g -c nonleafnode.h nonleafnode.cpp
g++ -g -c leafnode.h leafnode.cpp
g++ -o executeit bplustree.o nonleafnode.o leafnode.o
ld: warning: in /usr/local/lib/gcc/x86_64-apple-darwin10.8.0/4.6.4/libgcc.a, file was built for unsupported file format which is not the architecture being linked (x86_64)
As you can see, I have gcc version 4.6.4. I am not sure if this warning is a threat to the project working in any way, but I would like to know what this warning means and if it is a threat. It would be nice if I can do something to remove it, too. Thank you.
I have Mac OS X Version 10.6.8. The file /usr/local/lib/gcc/x86_64-apple-darwin10.8.0/4.6.4/libgcc.a has "10.8.0", and this version of gcc I installed must have screwed me over. I don't know if I can remove this warning by installing OS X 10.8.0, but I will consider this question answered for now. Thank you.