使用C++和stack/cabal编译Haskell软件包

Question

我想用一个软件包剪辑器http://hackage.haskell.org/package/clipper来检测复杂多边形的交集。这是一个C++包的FFI。如果您运行

cabal build --with-gcc=/usr/bin/g++

而不是其他，它工作正常。有没有办法将gcc选项放入cabal文件或者让我的堆栈项目使用g ++构建依赖项？

设置出于某种原因，$ PATH不起作用：

% cabal build --with-gcc=g++ 
Building clipper-0.0.1... 
Preprocessing library clipper-0.0.1... 
[1 of 1] Compiling Algebra.Clipper (dist/build/Algebra/Clipper.hs, dist/build/Algebra/Clipper.o) 
In-place registering clipper-0.0.1... 

% PATH=$(pwd):$PATH gcc 
g++: fatal error: no input files 
compilation terminated. 

% PATH=$(pwd):$PATH cabal build 
Building clipper-0.0.1... 
Preprocessing library clipper-0.0.1... 
In file included from Clipper.hsc:27:0: 
cbits/clipper.hpp:29:18: fatal error: vector: Dosiero aŭ dosierujo ne ekzistas 
compilation terminated. 
compiling dist/build/Algebra/Clipper_hsc_make.c failed (exit code 1) 
command was: /usr/bin/gcc -c dist/build/Algebra/Clipper_hsc_make.c -o dist/build/Algebra/Clipper_hsc_make.o -fno-stack-protector -D__GLASGOW_HASKELL__=710 -Dlinux_BUILD_OS=1 -Dx86_64_BUILD_ARCH=1 -Dlinux_HOST_OS=1 -Dx86_64_HOST_ARCH=1 -Icbits -Idist/build/autogen -include dist/build/autogen/cabal_macros.h -I/usr/local/haskell/ghc-7.10.2-x86_64/lib/ghc-7.10.2/base_GDytRqRVSUX7zckgKqJjgw/include -I/usr/local/haskell/ghc-7.10.2-x86_64/lib/ghc-7.10.2/integ_2aU3IZNMF9a7mQ0OzsZ0dS/include -I/usr/local/haskell/ghc-7.10.2-x86_64/lib/ghc-7.10.2/include -I/usr/local/haskell/ghc-7.10.2-x86_64/lib/ghc-7.10.2/include/ 

同样，改变Setup.hs建议，由@ErikR下面没有帮助。

% runghc Setup.hs build 
"Hello, I am running" 
fomg 
BuildFlags 
    { buildProgramPaths = [] 
    , buildProgramArgs = [] 
    , buildDistPref = Flag "dist" 
    , buildVerbosity = Flag Normal 
    , buildNumJobs = NoFlag 
    , buildArgs = [] 
} 
fimg 
BuildFlags 
    { buildProgramPaths = [ ("gcc" , "/usr/bin/g++") ] 
    , buildProgramArgs = [] 
    , buildDistPref = Flag "dist" 
    , buildVerbosity = Flag Normal 
    , buildNumJobs = NoFlag 
    , buildArgs = [] 
    } 
Building clipper-0.0.1... 
Preprocessing library clipper-0.0.1... 
In file included from Clipper.hsc:27:0: 
(etc) 

请注意，它在buildHook行崩溃，所以为了获得打印标志，我需要改变周围的顺序。

Answer 1

试试这个简单的定制Setup.hs文件：

import Distribution.Simple 
import System.Environment 

main = do 
    args <- getArgs 
    defaultMainArgs $ ["--with-gcc=c++"] ++ args 

原来的答案

一些想法：

（1）创建一个名为gcc一个包装脚本调用g++。将脚本尽早放在PATH中，以便运行gcc将运行脚本而不是真正的gcc。也许你只有在构建剪切器包时才有这个包装脚本。

（2）编写一个自定义的Setup.hs。

1. 修改build-type字段中clipper.cabal文件是Custom，而不是Simple

2. 更换Setup.hs与文件：

   import Distribution.Simple 
   import Distribution.Simple.Setup 
   import Distribution.Simple.LocalBuildInfo 
   import Distribution.PackageDescription 
   import Text.Show.Pretty 
   
   main = do 
       let hooks = simpleUserHooks 
   
        myBuild :: PackageDescription -> LocalBuildInfo -> UserHooks -> BuildFlags -> IO() 
        myBuild pkgd buildinfo uhooks flags = do 
        putStrLn $ ppShow flags 
        let flags' = flags { buildProgramPaths = [("gcc","g++")] ++ (buildProgramPaths flags) } 
        buildHook hooks pkgd buildinfo uhooks flags' 
        putStrLn $ ppShow flags' 
        hooks' = hooks { buildHook = myBuild } 
   
       defaultMainWithHooks hooks' 
   

注：文字的进口.Show.Pretty不是必需的，所以如果你没有安装它，你可以删除它和ppShow调用。

上述Setup.hs应该与调用cabal --with-gcc=g++具有相同的效果。