I'm trying to compile a simple c++ program that uses std::thread on eclipse kepler / mingw 4.8.1 and win32. I hope to move development to linux at some point after many years on windows development.
#include "test.h"
#include <thread>
#include <algorithm>
int main()
{
Test::CreateInstance();
std::thread(
[&]()
{
Test::I()->Output2();
}
);
Test::DestroyInstance();
return 0;
}
Ignoring the purpose of test (it's a singleton that just produces some output that I will expand upon, once I get the std::thread working!)
The g++ compiler settings I've set in Eclipse are:
-c -fmessage-length=0 -std=c++0x -Wc++0x-compat
And the preprocessor symbol I have defined is:
__GXX_EXPERIMENTAL_CXX0X__
Building complains that std::thread is not a member of std:
10:30:13 **** Incremental Build of configuration Debug for project test ****
Info: Internal Builder is used for build
g++ -D__GXX_EXPERIMENTAL_CXX0X__ -O0 -g3 -Wall -c -fmessage-length=0 -std=c++0x -Wc++0x-compat -o main.o "..\\main.cpp"
..\main.cpp: In function 'int main()':
..\main.cpp:11:2: error: 'thread' is not a member of 'std'
std::thread(
^
Can someone suggest what I might be missing to get this compiling correctly?
Plain MinGW cannot support std::thread. You will need to use a MinGW-w64 toolchain (such as those shipped with Qt 5) that has "posix" threading enabled, so that libstdc++ exposes the <thread>, <mutex> and <future> functionality.
You can find an installer here, but you can also try just replacing the whole mingw toolchain root folder with one of these packages. You can choose 32- or 64-bit, remember to select threads-posix if you want to play with std::thread and friends. No special compiler options other than the ones you already have are needed. I do suggest using -std=c++11 if you don't need GCC 4.6 compatibility.
I had the same problem, though I worked with Cygwin compiler instead. What I did was to define the symbol __cplusplus with the value 201103L for the preprocessor. Also I'd used the flag -std=c++11 for the compiler. This settings have to be made for All configurations (Debug & Release).
Another thing that you may check is that you have properly installed the compiler, verify your compiler instalation as explained by rubenvb.
See here for a native implementation that can be added to any C++11 version of MinGW:
https://github.com/meganz/mingw-std-threads
It is a header-only library, so you just need to include the headers in your project and you will get C++11 threads and synchronization primitives.
Related
I am using Atom as my IDE, my current __cplusplus = 201402 which is C++14 and my compiler is g++ (GCC) 9.2.0.
How do I upgrade to C++17 or C++20?
Everything I've searched up involves using another IDE (Microsoft Visual Studio).
You don't "upgrade" to newer C++ standards.
You can upgrade compiler to newer version supporting latest standards.
As of today, most compilers are set to C++14 by default.
To change it you need to pass additional argument during compilation.
For example, to compile hello.cpp with GCC for C++17 you need to execute
g++ -std=c++17 hello.cpp
You need to check how to pass compiler flags (or set standards) in your IDE / editor / build system.
I'm not familiar with Atom, but I've found this:
In the settings, click on Packages, then search for gpp-compiler. You should see a settings button – click on it and edit the command line options to suit your needs.
Do-it-yourself:
#include <iostream>
int main(void) {
std::cout << __cplusplus;
return 0;
}
Compile this firstly with the following command:
$ g++ -o main main.cpp && ./main
Thereafter:
g++ -o main main.cpp -std=c++17 && ./main
You'll get to know the differences. Note that if you're unable to use -std=c++20 flag, it clearly means that your compiler doesn't supports C++20 standard.
I'm trying to compile a simple c++ program that uses std::thread on eclipse kepler / mingw 4.8.1 and win32. I hope to move development to linux at some point after many years on windows development.
#include "test.h"
#include <thread>
#include <algorithm>
int main()
{
Test::CreateInstance();
std::thread(
[&]()
{
Test::I()->Output2();
}
);
Test::DestroyInstance();
return 0;
}
Ignoring the purpose of test (it's a singleton that just produces some output that I will expand upon, once I get the std::thread working!)
The g++ compiler settings I've set in Eclipse are:
-c -fmessage-length=0 -std=c++0x -Wc++0x-compat
And the preprocessor symbol I have defined is:
__GXX_EXPERIMENTAL_CXX0X__
Building complains that std::thread is not a member of std:
10:30:13 **** Incremental Build of configuration Debug for project test ****
Info: Internal Builder is used for build
g++ -D__GXX_EXPERIMENTAL_CXX0X__ -O0 -g3 -Wall -c -fmessage-length=0 -std=c++0x -Wc++0x-compat -o main.o "..\\main.cpp"
..\main.cpp: In function 'int main()':
..\main.cpp:11:2: error: 'thread' is not a member of 'std'
std::thread(
^
Can someone suggest what I might be missing to get this compiling correctly?
Plain MinGW cannot support std::thread. You will need to use a MinGW-w64 toolchain (such as those shipped with Qt 5) that has "posix" threading enabled, so that libstdc++ exposes the <thread>, <mutex> and <future> functionality.
You can find an installer here, but you can also try just replacing the whole mingw toolchain root folder with one of these packages. You can choose 32- or 64-bit, remember to select threads-posix if you want to play with std::thread and friends. No special compiler options other than the ones you already have are needed. I do suggest using -std=c++11 if you don't need GCC 4.6 compatibility.
I had the same problem, though I worked with Cygwin compiler instead. What I did was to define the symbol __cplusplus with the value 201103L for the preprocessor. Also I'd used the flag -std=c++11 for the compiler. This settings have to be made for All configurations (Debug & Release).
Another thing that you may check is that you have properly installed the compiler, verify your compiler instalation as explained by rubenvb.
See here for a native implementation that can be added to any C++11 version of MinGW:
https://github.com/meganz/mingw-std-threads
It is a header-only library, so you just need to include the headers in your project and you will get C++11 threads and synchronization primitives.
I'm trying to compile a simple c++ program that uses std::thread on eclipse kepler / mingw 4.8.1 and win32. I hope to move development to linux at some point after many years on windows development.
#include "test.h"
#include <thread>
#include <algorithm>
int main()
{
Test::CreateInstance();
std::thread(
[&]()
{
Test::I()->Output2();
}
);
Test::DestroyInstance();
return 0;
}
Ignoring the purpose of test (it's a singleton that just produces some output that I will expand upon, once I get the std::thread working!)
The g++ compiler settings I've set in Eclipse are:
-c -fmessage-length=0 -std=c++0x -Wc++0x-compat
And the preprocessor symbol I have defined is:
__GXX_EXPERIMENTAL_CXX0X__
Building complains that std::thread is not a member of std:
10:30:13 **** Incremental Build of configuration Debug for project test ****
Info: Internal Builder is used for build
g++ -D__GXX_EXPERIMENTAL_CXX0X__ -O0 -g3 -Wall -c -fmessage-length=0 -std=c++0x -Wc++0x-compat -o main.o "..\\main.cpp"
..\main.cpp: In function 'int main()':
..\main.cpp:11:2: error: 'thread' is not a member of 'std'
std::thread(
^
Can someone suggest what I might be missing to get this compiling correctly?
Plain MinGW cannot support std::thread. You will need to use a MinGW-w64 toolchain (such as those shipped with Qt 5) that has "posix" threading enabled, so that libstdc++ exposes the <thread>, <mutex> and <future> functionality.
You can find an installer here, but you can also try just replacing the whole mingw toolchain root folder with one of these packages. You can choose 32- or 64-bit, remember to select threads-posix if you want to play with std::thread and friends. No special compiler options other than the ones you already have are needed. I do suggest using -std=c++11 if you don't need GCC 4.6 compatibility.
I had the same problem, though I worked with Cygwin compiler instead. What I did was to define the symbol __cplusplus with the value 201103L for the preprocessor. Also I'd used the flag -std=c++11 for the compiler. This settings have to be made for All configurations (Debug & Release).
Another thing that you may check is that you have properly installed the compiler, verify your compiler instalation as explained by rubenvb.
See here for a native implementation that can be added to any C++11 version of MinGW:
https://github.com/meganz/mingw-std-threads
It is a header-only library, so you just need to include the headers in your project and you will get C++11 threads and synchronization primitives.
I'm trying to compile a simple c++ program that uses std::thread on eclipse kepler / mingw 4.8.1 and win32. I hope to move development to linux at some point after many years on windows development.
#include "test.h"
#include <thread>
#include <algorithm>
int main()
{
Test::CreateInstance();
std::thread(
[&]()
{
Test::I()->Output2();
}
);
Test::DestroyInstance();
return 0;
}
Ignoring the purpose of test (it's a singleton that just produces some output that I will expand upon, once I get the std::thread working!)
The g++ compiler settings I've set in Eclipse are:
-c -fmessage-length=0 -std=c++0x -Wc++0x-compat
And the preprocessor symbol I have defined is:
__GXX_EXPERIMENTAL_CXX0X__
Building complains that std::thread is not a member of std:
10:30:13 **** Incremental Build of configuration Debug for project test ****
Info: Internal Builder is used for build
g++ -D__GXX_EXPERIMENTAL_CXX0X__ -O0 -g3 -Wall -c -fmessage-length=0 -std=c++0x -Wc++0x-compat -o main.o "..\\main.cpp"
..\main.cpp: In function 'int main()':
..\main.cpp:11:2: error: 'thread' is not a member of 'std'
std::thread(
^
Can someone suggest what I might be missing to get this compiling correctly?
Plain MinGW cannot support std::thread. You will need to use a MinGW-w64 toolchain (such as those shipped with Qt 5) that has "posix" threading enabled, so that libstdc++ exposes the <thread>, <mutex> and <future> functionality.
You can find an installer here, but you can also try just replacing the whole mingw toolchain root folder with one of these packages. You can choose 32- or 64-bit, remember to select threads-posix if you want to play with std::thread and friends. No special compiler options other than the ones you already have are needed. I do suggest using -std=c++11 if you don't need GCC 4.6 compatibility.
I had the same problem, though I worked with Cygwin compiler instead. What I did was to define the symbol __cplusplus with the value 201103L for the preprocessor. Also I'd used the flag -std=c++11 for the compiler. This settings have to be made for All configurations (Debug & Release).
Another thing that you may check is that you have properly installed the compiler, verify your compiler instalation as explained by rubenvb.
See here for a native implementation that can be added to any C++11 version of MinGW:
https://github.com/meganz/mingw-std-threads
It is a header-only library, so you just need to include the headers in your project and you will get C++11 threads and synchronization primitives.
GoogleTest 1.6 with Cygwin 1.7: 'fileno' was not declared in this scope
Error message when building a simple test on Factorial() function in Eclipse CDT:
Invoking: Cygwin C++ Compiler
g++ -std=c++0x -DGTEST_OS_CYGWIN=1 -I"E:\source\gtest-1.6.0\include" -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/challenge.d" -MT"src/challenge.d" -o "src/challenge.o" "../src/challenge.cpp"
In file included from E:\source\gtest-1.6.0\include/gtest/internal/gtest-internal.h:40:0,
from E:\source\gtest-1.6.0\include/gtest/gtest.h:57,
from ../src/challenge.cpp:11:
E:\source\gtest-1.6.0\include/gtest/internal/gtest-port.h: In function 'int testing::internal::posix::FileNo(FILE*)':
E:\source\gtest-1.6.0\include/gtest/internal/gtest-port.h:1589:51: error: 'fileno' was not declared in this scope
E:\source\gtest-1.6.0\include/gtest/internal/gtest-port.h:1595:57: error: 'strdup' was not declared in this scope
E:\source\gtest-1.6.0\include/gtest/internal/gtest-port.h:1627:71: error: 'fdopen' was not declared in this scope
Eclipse CDT 8.1 running gcc 4.7.3 on Cygwin 1.7.22
gTest 1.6 succesfully built including demo tests, with cmake 2.8.9 on Cygwin 1.7.22
I've linked the built lib with full path, E:\lib\gtest-1.6.0\Cygwin\libgtest.a
The following command option was added manually, got same error without it.
-DGTEST_OS_CYGWIN=1
Seems the errors have nothing to do with my code. Anyone using gTest with Eclipse and Cygwin?
Thank you,
unsigned long Factorial(unsigned n) {
return n==0? 0 : n*Factorial(n-1);
}
// Tests factorial of 0.
TEST(FactorialTest, HandlesZeroInput) {
EXPECT_EQ(1, Factorial(0));
}
// Tests factorial of positive numbers.
TEST(FactorialTest, HandlesPositiveInput) {
EXPECT_EQ(1, Factorial(1));
EXPECT_EQ(2, Factorial(2));
EXPECT_EQ(6, Factorial(3));
EXPECT_EQ(40320, Factorial(8));
}
Setting the C++ standard to -std=gnu++0x rather than -std=c++0x, worked for me. You can try the statement:
g++ -std=gnu++0x -DGTEST_OS_CYGWIN=1 -I"E:\source\gtest-1.6.0\include" -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/challenge.d" -MT"src/challenge.d" -o "src/challenge.o" "../src/challenge.cpp"
Setting symbol (-DGTEST_OS_CYGWIN=1) has got nothing to do with this error.
Some functions go beyond the ANSI standard.
These are disabled when you use std=c++11 (or std=c++0x).
Among them are fdopen, fileno and strdup.
There are two possibilities to use them:
Use the GNU dialect (std=gnu++11).
If you want to compile without dialect and make a local exception, you can include stdio.h with the __STRICT_ANSI__ undefined. (see: Error "'fdopen' was not declared" found with g++ 4 that compiled with g++3)
I have tested both on Suse Linux Enterprise 11, MinGW and Cygwin.
Addition: Another (possibly better) way to access non-ANSI symbols would be to add
#define _POSIX_C_SOURCE 200809L
before the first #include in your file. This will give you access to most of the non-standard routines.
Some functions (e.g. realpath(...)) require
#define _BSD_SOURCE
to be inserted on top of your file.