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<p class="MsoNormal"><span lang="EN-US">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">If I compile my source code two time I would like to get the same binary. But currently when I run
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">echo "main = return ()" > c.hs && ghc -fforce-recomp c.hs && xxd c > c1.hex && ghc -fforce-recomp c.hs && xxd c > c2.hex && diff c1.hex c2.hex<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">my output is<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">[1 of 1] Compiling Main ( c.hs, c.o )<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Linking c ...<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">[1 of 1] Compiling Main ( c.hs, c.o )<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Linking c ...<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">55494c55494<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">< 00d8c50: 7400 6768 6333 3130 3830 5f30 2e63 0073 t.ghc31080_0.c.s<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">---<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">> 00d8c50: 7400 6768 6333 3130 3935 5f30 2e63 0073 t.ghc31095_0.c.s<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">So why does the binary differ? Is there a way to compile with ghc and get the same binary? Even though only one byte differ, the checksum (sha,md5,..) is completely changed… I’m running Linux and ghc 7.6.3.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Joakim <o:p></o:p></span></p>
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