#7655: 7.6.2 Segmentation Fault/Bus Error in large exponentation -------------------------------------+---------------------------------- Reporter: Doug310 | Owner: Type: bug | Status: infoneeded Priority: normal | Milestone: 7.8.4 Component: GHCi | Version: 7.8.1-rc1 Resolution: | Keywords: exponentiation Operating System: MacOS X | Architecture: x86_64 (amd64) Type of failure: GHCi crash | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: Differential Revisions: | -------------------------------------+---------------------------------- Comment (by croyd): Hi, I think I ran in to this issue running the following code (fibonacci matrix exponentiation) in ghci. It seems to happen every single time I execute it inside ghci, but never when using the full compiler (ghc --make). {{{#!hs module Matrix where data Matrix = Matrix Integer Integer Integer Integer deriving (Eq, Show) instance Num Matrix where fromInteger n = Matrix n n n n negate = undefined (+) = plusMatrix (*) = mulMatrix abs (Matrix a00 a01 a10 a11) = Matrix a00' a01' a10' a11' where a00' = abs a00 a01' = abs a01 a10' = abs a10 a11' = abs a11 signum = undefined plusMatrix :: Matrix -> Matrix -> Matrix (Matrix a00 a01 a10 a11) `plusMatrix` (Matrix b00 b01 b10 b11) = Matrix (a00 + b00) (a01 + b01) (a10 + b10) (a11 + b11) mulMatrix :: Matrix -> Matrix -> Matrix (Matrix a00 a01 a10 a11) `mulMatrix` (Matrix b00 b01 b10 b11) = Matrix a00' a01' a10' a11' where a00' = a00 * b00 + a01 * b10 a01' = a00 * b01 + a01 * b11 a10' = a10 * b00 + a11 * b10 a11' = a10 * b10 + a11 * b11 fib4 :: Integer -> Integer fib4 0 = 0 fib4 n = case f ^ n of Matrix _ fn _ _ -> fn where f = Matrix 1 1 1 0 main = do print $ fib4 1000 -- ok putStrLn $ replicate 80 '-' print $ fib4 10000 -- ok putStrLn $ replicate 80 '-' print $ fib4 1000000 -- bus error: 10 }}} crash report: {{{ Process: ghc [30070] Path: /usr/local/lib/ghc-7.8.3/bin/ghc Identifier: ghc Version: ??? Code Type: X86-64 (Native) Parent Process: bash [97679] User ID: 501 Date/Time: 2014-07-27 15:30:12.594 -0500 OS Version: Mac OS X 10.8.4 (12E55) Report Version: 10 Crashed Thread: 1 Exception Type: EXC_BAD_ACCESS (SIGBUS) Exception Codes: KERN_PROTECTION_FAILURE at 0x0000000115341000 VM Regions Near 0x115341000: MALLOC metadata 000000011532c000-0000000115341000 [ 84K] rw-/rwx SM=COW --> MALLOC guard page 0000000115341000-0000000115342000 [ 4K] ---/rwx SM=NUL Stack 0000000115342000-0000000115343000 [ 4K] ---/rwx SM=NUL Thread 0:: Dispatch queue: com.apple.main-thread 0 libsystem_kernel.dylib 0x00007fff8d3340fa __psynch_cvwait + 10 1 libsystem_c.dylib 0x00007fff8d853fe9 _pthread_cond_wait + 869 2 libHSrts_thr-ghc7.8.3.dylib 0x00000001152bde86 waitCondition + 6 3 libHSrts_thr-ghc7.8.3.dylib 0x0000000115297752 yieldCapability + 354 4 libHSrts_thr-ghc7.8.3.dylib 0x00000001152a7f26 schedule + 502 5 libHSrts_thr-ghc7.8.3.dylib 0x00000001152a7d17 scheduleWaitThread + 167 6 libHSrts_thr-ghc7.8.3.dylib 0x00000001152a3eea hs_main + 138 7 ghc 0x000000010e8c6d73 main + 115 8 ghc 0x000000010e7ddc34 start + 52 Thread 1 Crashed: 0 libHSinteger-gmp-0.5.1.0-ghc7.8.3.dylib 0x0000000115178811 __gmpn_addlsh2_n + 289 1 libHSinteger-gmp-0.5.1.0-ghc7.8.3.dylib 0x00000001151b87aa __gmpn_toom43_mul + 202 2 libHSinteger-gmp-0.5.1.0-ghc7.8.3.dylib 0x0000000115196c6b __gmpn_mul + 1835 3 libHSinteger-gmp-0.5.1.0-ghc7.8.3.dylib 0x000000011519d795 __gmpn_tdiv_qr + 3221 4 libHSinteger-gmp-0.5.1.0-ghc7.8.3.dylib 0x00000001151b4b88 __gmpz_tdiv_qr + 408 5 libHSinteger-gmp-0.5.1.0-ghc7.8.3.dylib 0x0000000115175b9f integer_cmm_quotRemIntegerzh + 207 6 libHSbase-4.7.0.1-ghc7.8.3.dylib 0x0000000114af08f0 c6Zm_info + 56 Thread 2: 0 libsystem_kernel.dylib 0x00007fff8d334f96 poll + 10 1 libHSbase-4.7.0.1-ghc7.8.3.dylib 0x0000000114be1444 cbep_info + 660 2 ??? 0x0000000115727e83 0 + 4654792323 Thread 3: 0 libsystem_kernel.dylib 0x00007fff8d334d16 kevent + 10 1 libHSbase-4.7.0.1-ghc7.8.3.dylib 0x0000000114ba3de5 cbpC_info + 173 2 libHSbase-4.7.0.1-ghc7.8.3.dylib 0x0000000114ba4908 cbuZ_info + 56 Thread 4: 0 libsystem_kernel.dylib 0x00007fff8d3340fa __psynch_cvwait + 10 1 libsystem_c.dylib 0x00007fff8d853fe9 _pthread_cond_wait + 869 2 libHSrts_thr-ghc7.8.3.dylib 0x00000001152bde86 waitCondition + 6 3 libHSrts_thr-ghc7.8.3.dylib 0x0000000115297752 yieldCapability + 354 4 libHSrts_thr-ghc7.8.3.dylib 0x00000001152a7f26 schedule + 502 5 libHSrts_thr-ghc7.8.3.dylib 0x00000001152a88bd scheduleWorker + 13 6 libsystem_c.dylib 0x00007fff8d84f7a2 _pthread_start + 327 7 libsystem_c.dylib 0x00007fff8d83c1e1 thread_start + 13 Thread 1 crashed with X86 Thread State (64-bit): rax: 0x0000000000000000 rbx: 0x000000000000045b rcx: 0xfffffffffffffe84 rdx: 0x00000001154a0b68 rdi: 0x0000000115341bd0 rsi: 0x000000011549c5b8 rbp: 0x0000000115338f40 rsp: 0x0000000115338ec8 r8: 0x0000000000000001 r9: 0x0000000000000003 r10: 0x0000000000000003 r11: 0x0000000000000003 r12: 0xa37d223548939bc0 r13: 0x45cb5efb1fce45fd r14: 0x1ad82f94a68b146b r15: 0xaef755979088a4bb rip: 0x0000000115178811 rfl: 0x0000000000010286 cr2: 0x0000000115341000 Logical CPU: 2 Binary Images: 0x10e7dc000 - 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0x7fff8848afff libiconv.2.dylib (34) <FEE8B996-EB44-37FA-B96E-D379664DEFE1> /usr/lib/libiconv.2.dylib 0x7fff889a9000 - 0x7fff88ac192f libobjc.A.dylib (532.2) <90D31928 -F48D-3E37-874F-220A51FD9E37> /usr/lib/libobjc.A.dylib 0x7fff89440000 - 0x7fff89442fff libquarantine.dylib (52.1) <143B726E-DF47-37A8-90AA-F059CFD1A2E4> /usr/lib/system/libquarantine.dylib 0x7fff89696000 - 0x7fff896c4ff7 libsystem_m.dylib (3022.6) <B434BE5C-25AB-3EBD-BAA7-5304B34E3441> /usr/lib/system/libsystem_m.dylib 0x7fff896c5000 - 0x7fff896e7ff7 libxpc.dylib (140.43) <70BC645B-6952-3264-930C-C835010CCEF9> /usr/lib/system/libxpc.dylib 0x7fff8ac55000 - 0x7fff8ac5afff libcompiler_rt.dylib (30) <08F8731D-5961-39F1-AD00-4590321D24A9> /usr/lib/system/libcompiler_rt.dylib 0x7fff8bb78000 - 0x7fff8bb8dff7 libdispatch.dylib (228.23) <D26996BF-FC57-39EB-8829-F63585561E09> /usr/lib/system/libdispatch.dylib 0x7fff8d2d2000 - 0x7fff8d321ff7 libcorecrypto.dylib (106.2) <CE0C29A3-C420-339B-ADAA-52F4683233CC> /usr/lib/system/libcorecrypto.dylib 0x7fff8d322000 - 0x7fff8d33dff7 libsystem_kernel.dylib (2050.24.15) <A9F97289-7985-31D6-AF89-151830684461> /usr/lib/system/libsystem_kernel.dylib 0x7fff8d83b000 - 0x7fff8d907ff7 libsystem_c.dylib (825.26) <4C9EB006-FE1F-3F8F-8074-DFD94CF2CE7B> /usr/lib/system/libsystem_c.dylib 0x7fff8d9d9000 - 0x7fff8d9d9fff libkeymgr.dylib (25) <CC9E3394-BE16-397F-926B-E579B60EE429> /usr/lib/system/libkeymgr.dylib 0x7fff8dce2000 - 0x7fff8dce3fff libDiagnosticMessagesClient.dylib (8) <8548E0DC-0D2F-30B6-B045-FE8A038E76D8> /usr/lib/libDiagnosticMessagesClient.dylib 0x7fff8dd40000 - 0x7fff8dd41ff7 libsystem_sandbox.dylib (220.3) <B739DA63-B675-387A-AD84-412A651143C0> /usr/lib/system/libsystem_sandbox.dylib 0x7fff8eb49000 - 0x7fff8eb4aff7 libdnsinfo.dylib (453.19) <14202FFB-C3CA-3FCC-94B0-14611BF8692D> /usr/lib/system/libdnsinfo.dylib 0x7fff8eb4b000 - 0x7fff8eb70ff7 libc++abi.dylib (26) <D86169F3-9F31-377A-9AF3-DB17142052E4> /usr/lib/libc++abi.dylib 0x7fff8ebc5000 - 0x7fff8ec2dff7 libc++.1.dylib (65.1) <20E31B90-19B9-3C2A-A9EB-474E08F9FE05> /usr/lib/libc++.1.dylib 0x7fff8f14c000 - 0x7fff8f152fff libmacho.dylib (829) /usr/lib/system/libmacho.dylib 0x7fff8f26d000 - 0x7fff8f2a5fff libncurses.5.4.dylib (37.3) <68D5B5F5-8252-3F1E-AFF1-C6AFE145DBC1> /usr/lib/libncurses.5.4.dylib 0x7fff8f4ef000 - 0x7fff8f4f6fff libcopyfile.dylib (89) <876573D0-E907-3566-A108-577EAD1B6182> /usr/lib/system/libcopyfile.dylib 0x7fff8f746000 - 0x7fff8f77cfff libsystem_info.dylib (406.17) <4FFCA242-7F04-365F-87A6-D4EFB89503C1> /usr/lib/system/libsystem_info.dylib 0x7fff8f77d000 - 0x7fff8f783ff7 libunwind.dylib (35.1) <21703D36 -2DAB-3D8B-8442-EAAB23C060D3> /usr/lib/system/libunwind.dylib External Modification Summary: Calls made by other processes targeting this process: task_for_pid: 0 thread_create: 0 thread_set_state: 0 Calls made by this process: task_for_pid: 0 thread_create: 0 thread_set_state: 0 Calls made by all processes on this machine: task_for_pid: 11291 thread_create: 1 thread_set_state: 0 VM Region Summary: ReadOnly portion of Libraries: Total=159.5M resident=138.3M(87%) swapped_out_or_unallocated=21.2M(13%) Writable regions: Total=52.5M written=21.6M(41%) resident=23.9M(46%) swapped_out=0K(0%) unallocated=28.6M(54%) REGION TYPE VIRTUAL =========== ======= MALLOC 18.2M MALLOC guard page 16K STACK GUARD 56.0M Stack 10.0M VM_ALLOCATE 19.0M __DATA 5892K __LINKEDIT 93.8M __TEXT 65.7M shared memory 12K =========== ======= TOTAL 268.5M }}} $ ghc --info {{{ [("Project name","The Glorious Glasgow Haskell Compilation System") ,("GCC extra via C opts"," -fwrapv") ,("C compiler command","/usr/local/bin/gcc") ,("C compiler flags"," -m64 -fno-stack-protector") ,("C compiler link flags"," -m64") ,("Haskell CPP command","/usr/local/bin/gcc") ,("Haskell CPP flags","-E -undef -traditional ") ,("ld command","/usr/bin/ld") ,("ld flags"," -arch x86_64") ,("ld supports compact unwind","YES") ,("ld supports build-id","NO") ,("ld supports filelist","YES") ,("ld is GNU ld","NO") ,("ar command","/usr/bin/ar") ,("ar flags","clqs") ,("ar supports at file","NO") ,("touch command","touch") ,("dllwrap command","/bin/false") ,("windres command","/bin/false") ,("libtool command","libtool") ,("perl command","/usr/bin/perl") ,("target os","OSDarwin") ,("target arch","ArchX86_64") ,("target word size","8") ,("target has GNU nonexec stack","False") ,("target has .ident directive","True") ,("target has subsections via symbols","True") ,("Unregisterised","NO") ,("LLVM llc command","llc") ,("LLVM opt command","opt") ,("Project version","7.8.3") ,("Booter version","7.6.3") ,("Stage","2") ,("Build platform","x86_64-apple-darwin") ,("Host platform","x86_64-apple-darwin") ,("Target platform","x86_64-apple-darwin") ,("Have interpreter","YES") ,("Object splitting supported","NO") ,("Have native code generator","YES") ,("Support SMP","YES") ,("Tables next to code","YES") ,("RTS ways","l debug thr thr_debug thr_l thr_p dyn debug_dyn thr_dyn thr_debug_dyn l_dyn thr_l_dyn") ,("Support dynamic-too","YES") ,("Support parallel --make","YES") ,("Dynamic by default","NO") ,("GHC Dynamic","YES") ,("Leading underscore","YES") ,("Debug on","False") ,("LibDir","/usr/local/lib/ghc-7.8.3") ,("Global Package DB","/usr/local/lib/ghc-7.8.3/package.conf.d") ] }}} $ gcc --version {{{ gcc (GCC) 4.9.0 20140302 (experimental) Copyright (C) 2014 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. }}} Please let me know if there's more I can do to help. I'd be willing to try and track down the issue myself, but I'm afraid I know next to nothing about ghc and it would probably take a lot more work helping me than it would to fix the issue otherwise. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/7655#comment:30 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler