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我从一个动态库(这里只是zlibVersion
)有一些C函数,我想从cabal包中的捆绑C代码调用。在这里,我将它直接称为外部导入,并通过捆绑的C代码间接地将其称为后者,即使在前者成功后,后者也会崩溃ghci。从c-sources调用动态库失败ghci
Main.hs:
module Main (main) where
import Foreign.C.String (CString, peekCString)
foreign import ccall "foreign_test" foreignTest :: IO()
foreign import ccall "zlibVersion" zlibVersion :: IO CString
main :: IO()
main = do
zlibVersion >>= peekCString >>= putStrLn
foreignTest
foreign_test.c:
#include <stdio.h>
#include <zlib.h>
void foreign_test() {
puts(zlibVersion());
}
它正常工作,从编译的二进制:
$ cabal build
$ dist/build/cabal-extra-libs-test/cabal-extra-libs-test
1.2.5
1.2.5
但间接调用崩溃GHCI:
$ cabal repl
Preprocessing executable 'cabal-extra-libs-test' for
cabal-extra-libs-test-0.1.0.0...
GHCi, version 7.10.3: http://www.haskell.org/ghc/ :? for help
[1 of 1] Compiling Main (Main.hs, interpreted)
Ok, modules loaded: Main.
*Main> main
1.2.5
dyld: lazy symbol binding failed: Symbol not found: _zlibVersion
Referenced from: /var/folders/pz/920gzhqn01q8d6vjkvy1yvdr0000gn/T/ghc6850_0/libghc_1.dylib
Expected in: flat namespace
dyld: Symbol not found: _zlibVersion
Referenced from: /var/folders/pz/920gzhqn01q8d6vjkvy1yvdr0000gn/T/ghc6850_0/libghc_1.dylib
Expected in: flat namespace
阴谋,特库-test.cabal:
name: cabal-extra-libs-test
version: 0.1.0.0
build-type: Simple
cabal-version: >=1.10
executable cabal-extra-libs-test
default-language: Haskell2010
main-is: Main.hs
build-depends: base
c-sources: foreign_test.c
extra-libraries: z
GHC是7.10.3与OS X 10.11.5小集团安装1.24.0.0。用stack和stack ghci构建同样的崩溃。
从'nm'的输出中,OS X在符号上使用下划线前缀。 7.10.3版本来自堆栈,我认为它使用官方的GHC版本。 GHC 8.0.1确实没有问题! –