Windows: stack exec foo works, foo.exe does not

[rubenmoor]

On windows stack build and stack exec foo works (which is great, btw). My program is running.

However, after stack install the execution of the executable file fails.

.\foo.exe -> complaint about missing library "libstdc++-6.dll"

I have no understanding of what stack exec does in windows (magic?). Any hint to what's going on?

[snoyberg]

Most likely Windows is not able to find the necessary C++ libraries from the standard prompt because they're not on your PATH. stack exec works because it's modifying the PATH to include extra things. Options here would be:

• Copy the relevant .dll files to something on your PATH
• Modify your PATH to include extra directories

In theory, stack could copy some DLLs over to the output directory for you, but that seems out-of-scope for what it's doing.

[rubenmoor]

Cool, thanks. I assume these libraries are created by stack during stack build. Where are they stored, i.e. what directories to include in my PATH?

[snoyberg]

Actually, they're not, they're shipped with GHC (and, theoretically in some cases, MSYS). The easiest way to find them is stack exec which. On my system, for instance:

>stack exec which libstdc++-6.dll
/c/Users/Michael/AppData/Local/Programs/stack/i386-windows/ghc-7.8.4/mingw/bin/libstdc++-6.dll

[snoyberg]

If that turns out to resolve it for you, would you be able to add a FAQ entry on the Wiki about this?

[radix]

perhaps an idea for a future plugin: bundle up a self-contained windows executable or installer?

[snoyberg]

Sounds like what we're doing with docker. Mind opening as a separate issue?
I don't want to lose track of it.

On Fri, Jun 26, 2015, 6:28 PM Christopher Armstrong <
[email protected]> wrote:

perhaps an idea for a future plugin: bundle up a self-contained windows
executable or installer?

—
Reply to this email directly or view it on GitHub
#425 (comment)
.

[rubenmoor]

If that turns out to resolve it for you, would you be able to add a FAQ entry on the Wiki about this?

Done

[snoyberg]

Thanks!