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copied!<p>As of ghc-7, the default mode is <code>--make</code>. You want to create a library, so you have to tell GHC with the <code>-c</code> flag. You don't need the <code>-no-hs-main</code> then.</p> <pre><code> ghc -c TestLib.hs -o test.o </code></pre> <p>works.</p> <p>An example:</p> <h3>clib.h:</h3> <pre class="lang-c prettyprint-override"><code>int doTest(void); </code></pre> <h3>clib.c:</h3> <pre class="lang-c prettyprint-override"><code>#include "clib.h" int doTest(void){ return 42; } </code></pre> <h3>TestLib.hs:</h3> <pre><code>{-# LANGUAGE ForeignFunctionInterface #-} module TestLib where foreign export ccall test_me :: IO (Int) foreign import ccall "clib.h" doTest :: IO ( Int ) test_me = doTest </code></pre> <h3>libtest.c:</h3> <pre class="lang-c prettyprint-override"><code>#include <stdio.h> #include "TestLib_stub.h" int main(int argc, char *argv[]) { hs_init(&argc, &argv); printf("%d\n", test_me()); hs_exit(); return 0; } </code></pre> <h3>Compilation and execution:</h3> <pre><code>$ ghc -c -o clib.o clib.c $ ar -r -s libclib.a clib.o ar: creating libclib.a $ ghc TestLib.hs -c -o tlib.o $ ar -r -s libtlib.a tlib.o ar: creating libtlib.a $ ghc -o nltest libtest.c -no-hs-main -L. -ltlib -lclib $ ./nltest 42 </code></pre> <p>Note: That works as such with ghc >= 7.2; for ghc-7.0.*, you must also compile the generated <code>TestLib_stub.c</code> file and link with <code>TestLib_stub.o</code>.</p> <p>The important point is to tell ghc <strong>not</strong> to link when creating the libraries, only when finally the executable is created.</p>

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