When compiling a package (cabal or stack doesn't matter) or launching GHCi while running a kernel with GrSec and PaX patches, GHC segfaults because GrSec denies an RWX mmap. Some packages do compile successfully, but others (such as optparse-applicative) don't. Launching GHCi always results in a segfault. I've tried mounting /tmp as executable (as described eg. [here](http://stackoverflow.com/questions/6103510/ghc-cabal-install-hamlet-fails-with-an-obscure-error)), but that didn't do anything. Here's the output of ghc when compiling the optparse-applicative package: ``` Building optparse-applicative-0.13.0.0... Preprocessing library optparse-applicative-0.13.0.0... [ 1 of 15] Compiling Options.Applicative.Help.Pretty ( Options/Applicative/Help/Pretty.hs, dist/build/Options/Applicative/Help/Pretty.o ) [ 2 of 15] Compiling Options.Applicative.Help.Chunk ( Options/Applicative/Help/Chunk.hs, dist/build/Options/Applicative/Help/Chunk.o ) [ 3 of 15] Compiling Options.Applicative.Help.Types ( Options/Applicative/Help/Types.hs, dist/build/Options/Applicative/Help/Types.o ) [ 4 of 15] Compiling Options.Applicative.Types ( Options/Applicative/Types.hs, dist/build/Options/Applicative/Types.o ) [ 5 of 15] Compiling Options.Applicative.Internal ( Options/Applicative/Internal.hs, dist/build/Options/Applicative/Internal.o ) [ 6 of 15] Compiling Options.Applicative.Common ( Options/Applicative/Common.hs, dist/build/Options/Applicative/Common.o ) [ 7 of 15] Compiling Options.Applicative.Help.Core ( Options/Applicative/Help/Core.hs, dist/build/Options/Applicative/Help/Core.o ) ghc: mmap 131072 bytes at (nil): Operation not permitted ghc: Try specifying an address with +RTS -xm<addr> -RTS Segmentation fault (core dumped) ``` GrSec log in dmesg: ``` [15873.000867] grsec: denied RWX mmap of <anonymous mapping> by /usr/lib/ghc-8.0.1/bin/ghc[ghc_worker:16494] uid/euid:1000/1000 gid/egid:1000/1000, parent /usr/bin/cabal[cabal:16486] uid/euid:1000/1000 gid/egid:1000/1000 [15873.001018] ghc_worker[16494]: segfault at 0 ip 000003b6c3a7167f sp 000002b6c23d8e50 error 6 in libHSrts_thr-ghc8.0.1.so[3b6c3a4f000+62000] ``` And here's the one for ghci: ``` $ ghci GHCi, version 8.0.1: http://www.haskell.org/ghc/ :? for help ghc: mmap 131072 bytes at (nil): Operation not permitted ghc: Try specifying an address with +RTS -xm<addr> -RTS Segmentation fault (core dumped) $ echo $? 139 ``` GrSec complained here with: ``` [14756.354725] grsec: denied RWX mmap of <anonymous mapping> by /usr/lib/ghc-8.0.1/bin/ghc[ghc:15883] uid/euid:1000/1000 gid/egid:1000/1000, parent /usr/bin/xonsh[xonsh:15879] uid/euid:1000/1000 gid/egid:1000/1000 [14756.354875] ghc[15883]: segfault at 0 ip 00000379c0e0b67f sp 000003f0b7278ce0 error 6 in libHSrts_thr-ghc8.0.1.so[379c0de9000+62000] ```