How to install nan.h on cygwin for g++? - c++

I can't build this simple program on cygwin:
#include <nan.h>
int main(){}
I get this error message:
$ g++ a.cpp
a.cpp:1:17: fatal error: nan.h: No such file or directory
compilation terminated.
Is it possible to install something on cygwin to get correct nan.h?

nan.h is an obsolete include of old gcc. On Cygwin NAN is defined on math.h
You can not use a software written in 2008
https://boutell.com/fracster-src/doubledouble/doubledouble.html
for such specific issue and just hope than it works out of the box.

You need to figure out where nan.h is located and than Add this path to the includes.
How to make g++ search for header files in a specific directory?

Related

Using Boost with C++?

I'm on Mac OS. I'm using Visual Studio Code.
I'm coding in C++. I recently installed the most recent version of Boost (1.76.0).
My file name: test.cpp
I've included this header in my file:
#include <boost/smart_ptr/scoped_ptr.hpp>
I'm compiling with this command:
g++ -std=c++11 test.cpp
My code won't compile. I keep getting this error:
'boost/smart_ptr/scoped_ptr.hpp' file not found
Question: What am I doing wrong?
Any help is greatly appreciated.
It's simple, whenever you use g++, you need to define your include folders with -I switch, in this case you can say:
g++ -Iboost -std=c++11 test.cpp
here boost is the name of the folder that your .h/.hpp files are inside it.
Update
Here is also a link that completely explain about how to use boost library: Link

cannot compile on mint 20.1: stdlib.h: No such file or directory

I am running a fresh install of Linux Mint 20.1 and I'n trying to compile a program for a GPS tracker, but it won't compile:
In file included from /usr/include/c++/9/bits/stl_algo.h:59,
from /usr/include/c++/9/algorithm:62,
from /usr/include/x86_64-linux-gnu/qt5/QtCore/qglobal.h:142,
from /usr/include/x86_64-linux-gnu/qt5/QtCore/QtCore:4,
from pch.h:27:
/usr/include/c++/9/cstdlib:75:15: fatal error: stdlib.h: No such file or directory
75 | #include_next <stdlib.h>
| ^~~~~~~~~~
compilation terminated.
I have installed a number of additional libraries (libusb, libmarble and a few others) and qmake.
Of course, stdlib.h is present on the system:
$ find /usr -name stdlib.h
/usr/include/x86_64-linux-gnu/bits/stdlib.h
/usr/include/bsd/stdlib.h
/usr/include/stdlib.h
/usr/include/c++/9/tr1/stdlib.h
/usr/include/c++/9/stdlib.h
/usr/include/tcl8.6/tcl-private/compat/stdlib.h
After looking at the other questions about this, I re-installed build-essential, which didn't help.
I re-installed the g++ compiler, no luck either.
I copied /usr/include/c++/9/stdlib.h to /usr/local/include, but it still complains about a missing stdlib.h
I changed the
#include_next <stdlib.h>
in cstdlib into
#include <stdlib.h>
only to find that the next include cannot find stdlib.h; changing that one produced the third include and so on. So that does not work either.
The program compiles and works on Slackware 14.2 by the way.
What am I missing?
Hello-world compiles normally; a simple program that does a malloc also compiles and runs.
I used to #anastaciu 's solution.
As it was a fresh install without much customization, I resorted to the option of a complete re-install. Bizarre that that works a bit, as it was already a fresh install. I still had to copy stdlib.h and a few others (math.h etc.) to /usr/local/lib` to get to the point where it would at least compile.

wchar.h no such file or directory

I've been trying to run simple c++ program
#include<iostream.h>
void main(){
cout<<"helloworld";
}
and the error I get is :
In file included from d:\mingw\lib\gcc\mingw32\6.3.0\include\c++\bits\postypes.h:40:0,
from d:\mingw\lib\gcc\mingw32\6.3.0\include\c++\iosfwd:40,
from d:\mingw\lib\gcc\mingw32\6.3.0\include\c++\ios:38,
from d:\mingw\lib\gcc\mingw32\6.3.0\include\c++\ostream:38,
from d:\mingw\lib\gcc\mingw32\6.3.0\include\c++\iostream:39,
from my.cpp:1:
d:\mingw\lib\gcc\mingw32\6.3.0\include\c++\cwchar:44:19: fatal error: wchar.h: No such file or directory
#include <wchar.h>
^
compilation terminated."
anyone know how to fix it ,I'm using the mingw to compile it.
Probably your MinGW is broken. Also, GCC 6.3.0 is very old.
Try a more recent MinGW or even better MinGW-w64.
A standalone build is available from http://winlibs.com/ with GCC 10.2.0 (both for Windows 32-bit and 64-bit).

'main.cpp:1: No include path in which to find iostream'

I just tried to compile simple Hello World in C++ using MinGW compiler in my Windows 10 command line. I used the command gcc main.cpp, and as I hit enter, I got this error: 'main.cpp:1: No include path in which to find iostream'.
What is the error and how do I fix it?
Use g++ main.cpp
The command gcc is setup for c compilation. It does not link the c++ standard library.
g++ does link c++ standard library.

Compilation error: "stddef.h: No such file or directory"

Whenever I try to compile this code it always ends up with this error:
In file included from /usr/include/wchar.h:6:0,
from /usr/lib/gcc/i686-pc-cygwin/4.9.2/include/c++/cwchar:44,
from /usr/lib/gcc/i686-pc-cygwin/4.9.2/include/c++/bits/postypes.h:40,
from /usr/lib/gcc/i686-pc-cygwin/4.9.2/include/c++/iosfwd:40,
from /usr/lib/gcc/i686-pc-cygwin/4.9.2/include/c++/ios:38,
from /usr/lib/gcc/i686-pc-cygwin/4.9.2/include/c++/ostream:38,
from /usr/lib/gcc/i686-pc-cygwin/4.9.2/include/c++/iostream:39,
from test.cpp:1:
/usr/include/sys/reent.h:14:20: fatal error: stddef.h: No such file or directory
#include <stddef.h>
^
compilation terminated.
The code I was trying to compile is:
#include <iostream>
using namespace std;
int main()
{
cout << "Hello World! :D";
return 0;
}
The error is because your gcc-core package and gcc-g++ are not of the same version. Either downgrade one of them to solve the problem or update both the libraries. Updating both the libraries is the recommended way.
I had this error on a fresh MinGW install, it had nothing to do with the installed packages mentioned in the current accepted answer by "Prasanth Karri". In my case the issue was caused by -nostdinc in my Makefile. I actually only needed that compiler flag when building for a different target platform (not when using MinGW) so I fixed the issue by removing that flag from MinGW builds.
When I was incorporating a software library written in C into an existing demo project(used a C++ mbed library) I encountered this problem. The demo project would compile just fine, but after I replaced the existing main file by my own, this error occurred.
At this point I hadn't yet thought about the fact that the mbed library that I needed was written in C++. My own main file was a .c file that #include the mbed header file. As a result I used my normal C source as if it was a C++ source. Therefore the compiler that was used to compile my main file was the C compiler.
This C compiler then encountered a #include of a module that actually does not exist (within its scope), as it's not a C++ compiler.
Only after I inspected the output of the build log I realised the various source C and C++ files were compiled by more that 1 compiler(the c++ compiler). The project used used compilers arm-none-eabi-c++ and arm-none-eabi-gcc (for embedded systems) as seen below.
Compile log:
Building file: ../anyfile.cpp
Invoking: MCU C++ Compiler
arm-none-eabi-c++ <A lot of arguments> "../anyfile.cpp"
Finished building: ../anyfile.cpp
Building file: ../main.c
Invoking: MCU C Compiler
arm-none-eabi-gcc <A lot of arguments> "../main.c"
In file included from <Project directory>\mbed/mbed.h:21:0,
from ../main.c:16:
<Project directory>\mbed/platform.h:25:19: fatal error: cstddef: No such file or directory
compilation terminated.
Of course in a C++ environment cstddef exists, but in a C environment cstddef doesn't exist, in stead it's just C's implementation of stddef.
In other words, cstddef does not exist in the C compiler.
I resolved this problem by renaming my main.c file to main.cpp and the rest of the code compiled smoothly too.
TLDR/Conclusion: When building a C++ project, avoid mixing C files with C++ files(sources and headers). If possible rename .c files to .cpp files to use the C++ compiler in stead of the C compiler where required.
In order to update it, follow below.
If you are on Windows, just run these on command prompt or powershell
Update the package list: mingw-get update
After updating the package list, run: mingw-get upgrade
Source: How to update GCC in MinGW on Windows?
This problem was solved for me as I installed codeblocks with mingw compiler then I copied the mingw folder from codeblocks to C drive and added
C\mingw\bin to the environment variables.
If you try to compile and see a message like, "fatal error: stddef.h: No such file or directory", the error is because your gcc-core and gcc-g++ packages are not of the same version. Rerun the Cygwin install and make sure that you select the highest numbered versions of gcc-core and gcc-g++.
After installing the C++ compiler with MinGW I encountered this problem as well. Apparently, you have to also install mingw32-base. Go to C:/MinGW/bin/mingw-get.exe (my path) and check it for installation at the Basic Setup tab.