I have msys2 installed separately from GHC. MinGW toolchain is installed inside of the msys environment. Now I'm running into issues with some native libraries that work when I use them outside of Haskell, but don't work when ran from Haskell code.
The problem is that commands like stack exec and stack repl prepend GHC's MinGW folders to the PATH and then you get things like one dynamic library being found in my msys installation, while it's dependency is first found in GHC's MinGW installation and the whole thing doesn't work.
Stack provides a skip-msys option to avoid using the msys environment that it installs, but as far as I can tell there's no way to skip the GHC-provided MinGW toolchain.
What can I do about this?
Related
I am developing on linux, but still release binaries for windows.
I recently started using readline though, and that has broken my windows builds. Initially it was unable to find the header files, so I copied them to the mingw includes folder. However I still get problems linking to the library (cannot find -lreadline).
How do I get the readline library so that I can link to it in linux when compiling for windows?
Readline should just work, on Windows, I think, although you'll probably have to compile it yourself and bundle it with your program.
You'll need a replacement for ncurses though: pdcurses should do the job for you. Again, you'll probably have to build it yourself, I think.
I am using Cygwin and have GCC (version 4.3.4 20090804 (release) 1 ) installed as Cygwin package.
When I built C code using GCC under Cygwin shell, the generated executable output file is a executable of type (PE32 executable for MS Windows (console) Intel 80386 32-bit) and it can only be executed/run under Cygwin shell, not as standalone .exe on Windows shell/command prompt. If I try to run it standalone on Windows command prompt it gives an error window saying "The program can't run because cygwin.dll is missing from your computer".
How can one make this .exe standalone, which can be executed on a command prompt of any other system or even in my own system?
I thought GCC under Cygwin would build a Linux executable (ELF 32-bit LSB executable), but it's not so. How can I use the gcc-cygwin combination to generate a *.out kind of Linux executable file?
Also, I cannot run a Linux executable generated on a Linux-gcc combination to execute under Cygwin.
Any pointers would be helpful.
Despite widespread rumours, Cygwin is not a Linux emulator, i.e. it doesn't produce or run Linux executables. For that you'll need a virtual machine or coLinux.
Instead, Cygwin is a compatibility layer, which aims to implement as much as possible of the POSIX and Linux APIs within Windows. This means that programs have to be compiled specifically for Cygwin, but it also means that it's better integrated with Windows, e.g. it lets you mix POSIX and Windows APIs in the same program.
It's the cygwin1.dll that provides that compatibility layer. If you build non-Cygwin executables using gcc-3's -mno-cygwin switch or one of the MinGW compilers, then of course you can't use any POSIX/Linux-specific APIs, and any such calls will need to be replaced with Windows equivalents.
Cygwin is an emulation layer. It allows UNIX code to run on Windows, if you compile it to use the emulation layer. To Windows it looks like any normal DLL and makes OS calls as normal. But when you compile against it, it shows the same functions as UNIX (well, POSIX technically, but UNIX it is)
1) When you build with cygwin, it automatically brings in this cygwin1.dll. This is the code that you need to make it look like UNIX. There are flags to make it not use this cygwin dll, meaning ignore the UNIX stuff and use native Windows calls. the -mno-cygwin flag will make the binary a native Windows binary, not using cygwin emulation. As others have said, you also need the -mwindows to make actual GUI apps using cygwin gcc.
2) To compile on one platform to run on another platform, you need what's called a cross compiler. You also need the libraries and headers for the other system. For what you want you'd need a cygwin-Linux cross compiler, Linux headers and libraries. It would probably be much easier to run Linux in a virtual machine than to set this up.
3) Remember that Cygwin just looks like UNIX to UNIX source code, not to Linux binaries. Once you compile things, the function calls are windows DLL calls. A cygwin program is still a Windows program (which is why you need a Windows style DLL to run it). Cygwin provides code for UNIX functions/system calls such as fork(), but even the method of calling them is now different. fork() now calls into a Windows DLL, not into a Linux kernel. It's still a very different system.
Not a complete answer, but I think I am able to give some pointers.
1) http://www.cygwin.com/cygwin-ug-net/programming.html says you should use -mswindows parameter. Take a look of MinGW.
2) You need a cross gcc to do this. By default cygwin gcc produces binaries linked against cygwin.dll.
3) That it because it is a linux binary. Easiest way is to recompile software in cygwin.
ad 1) There are currently three different mingw cross-compilers available for cygwin:
The old gcc3 -mno-cygwin is deprecated.
There are new mingw64 cross-compilers for 32 bit (mingw64-i686-gcc) and 64 bit windows targets (mingw64-x86_64-gcc).
There's no mingw-i686-gcc matching the official cygwin gcc4 compiler yet.
ad 2) There's no linux cross-compiler as cygwin package yet available. But people report success building such a cross-compiler by themselves.
ad 3) There's no cygwin cross-compiler as linux package available, but many mingw cross-compilers. Those mingw executables can also be executed under cygwin, though they cannot use cygwin features, just the simple windows runtime.
Correcting errors in others people posts:
-mswindows is not valid, -mwindows tells the linker to generate a GUI app without console.
-mno-cygwin is only valid for the old deprecated gcc3 compiler and is not supported anymore. Don't use it. With cygwin you should use ordinary host and target triples as with every other cross-compiler.
You need to have cygwin.dll in your path.
Or just use MinGW to compile native windows code without dependencies.
Since "gcc -mno-cygwin" does not work anymore, I was looking for a way to get a MinGW-targeted GCC running within my Cygwin environment. (Running a MSYS environment is not an option at this point.)
The Cygwin installer offers a package "gcc-mingw", which installs, among others:
lib/gcc/i686-pc-mingw32/3.4.4/cc1.exe
lib/gcc/i686-pc-mingw32/3.4.4/collect2.exe
lib/gcc/i686-pc-mingw32/3.4.4/crtbegin.o
lib/gcc/i686-pc-mingw32/3.4.4/crtend.o
What is absent is the "gcc" frontend. So, how do I actually invoke this compiler? I hopefully don't have to go through "cc1" manually, have I?
I googled, but couldn't find anything relevant on the subject...
As you already found, you can use gcc-3 with -mno-cygwin. The other possibility is to install the 32-bit and/or 64-bit toolchains from the MinGW-w64 project, which have been packaged for Cygwin very recently and hence are available through setup.exe now. Don't be put off by the rather confusing executable names: i686-w64-mingw32-gcc is the 32-bit compiler and x86_64-w64-mingw32-gcc is the 64-bit one.
Further searches revealed that the MinGW-targeted cross-compiler is not ready yet, and that one has to either use GCC v3 with -mno-cygwin, or install a cross-compiler manually (see link above)...
After installing the MingW g++ package for Cygwin (mingw64-x86_64-gcc-g++), I also struggled to figure out how to invoke it.
Thanks to this wiki, I found out the command was x86_64-w64-mingw32-g++. Then I did alias g++='x86_64-w64-mingw32-g++' and g++ started working as expected.
Cygwin homepage says that "Individual packages like bash, gcc, less, etc. are released independently of the DLL.".
Here you can find how to install gcc under cygwin, so you should also select gcc package during install not only gcc-mingw.
I've installed cygwin environment on Windows.
There is gcc 4.3. How to install gcc 4.4 in this environment?
The alternative is to build one yourself, but it will be extremely slow on cygwin. If you are a Linux user, you can build a native compiler (which runs in cmd.exe on windows, and produces native win32 binaries) on Linux. It is much faster (order of magnitude faster in my experience).
Otherwise, mingw is a good solution, although in my experience, the binary from equation.com work better for gcc 4.4 (there is no official gcc 4.4 from MinGW yet)
If you don't need the cygwin environment for special reasons, I'd go for Mingw with the gcc 4.4. You can find builds on: http://www.tdragon.net/recentgcc/.
Reading the MinGW FAQ, reveals that its possible to pass requests to use the MinGW binaries instead of the ones shipped with Cygwin.
For those who would like to use the Cygwin environment for development, yet generate non-Cygwin-dependant executables, a much easier option to "-mno-cygwin" does exist. Simply install Cygwin and the MinGW distribution in separate directories (i.e. "C:\CYGWIN" and "C:\MINGW"), and make sure that the "/bin" subdirectory beneath your MinGW installation comes before Cygwin's "/bin" subdirectory in your PATH environment variable (i.e. "PATH=%PATH%;C:\MINGW\BIN;C:\CYGWIN\BIN"). This will allow you access to all the UNIX tools you want, while ensuring that the instance of GCC used is the MinGW version. %%%
Bear in mind that within the "/etc/profile" file, Cygwin by default places "/usr/local/bin", "/usr/bin", and "/bin" ahead of your system-level PATH. Therefore, it is not enough to have the MinGW's "/bin" ahead of Cygwin in your Windows path... it must also be set to come first within the Cygwin environment (either by modifying "/etc/profile" or setting it manually).
I downloaded the latest Boost Jam binary from SourceForge and I'm using the command:
bjam toolset=gcc --build-type=complete stage
I've installed Cygwin along with the GCC compiler. While the command produces a stage/lib directory, I cannot find the thread library that I'm using in Linux. Boost Jam takes a while to run, so there could have been errors along the way. Can anyone guess as to why I don't have the thread library? Is there a specific command I can run in an attempt to only build the thread library? Thanks!
You most definitely need to check for, and provide the error messages. You can also try passing either threadapi=pthread or threadapi=win32 to Boost.Build invocation.
In general, using the GNU/Kernel32.dll operating system, sometimes referred to as Cygwin, is risky business. Will using the native port of gcc, from mingw, be sufficient for you?