September 2014 - ghc-tickets

[GHC] #8419: add rawSystem variant that takes an environment
by GHC 18 Nov '14

18 Nov '14

#8419: add rawSystem variant that takes an environment -------------------------------------+------------------------------------- Reporter: dagit | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: libraries/process | Version: 7.6.3 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | -------------------------------------+------------------------------------- rawSystem properly handles the case of ^C while waiting. Instead of requiring people to recreate this behavior when using runProcess, it would be good if we add and export a rawSystemWithEnv or directly export syncProcess. See for example: https://github.com/haskell/cabal/issues/1448 -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8419> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 2

[GHC] #8420: Spurious dynamic library dependencies
by GHC 18 Nov '14

18 Nov '14

#8420: Spurious dynamic library dependencies ------------------------------------+--------------------------------- Reporter: AndreasVoellmy | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Keywords: | Operating System: MacOS X Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+--------------------------------- It should be possible to have an executable A that depends on dynamic library B which in turn depends on dynamic library C, without A directly depending on C. {{{ A --> B --> C }}} Unfortunately, GHC 7.6.3 does not seem to allow this. Instead it copies the dependencies of B to dependencies of A, so that we get {{{ A -> B,C and B --> C }}} This is unfortunately, because running A will cause the loader to locate C based on the rpaths (assuming we are using rpaths to locate dynamic libraries), whereas only B should know how to get to C from B. The problem seems to be that ghc copies all the library dependencies of B (presumably from the package specification of B) as library dependencies of the A. I verified the problem in GHC 7.6.3, but haven't tried in HEAD yet. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8420> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #8447: A combination of type-level comparison and subtraction does not work for 0
by GHC 18 Nov '14

18 Nov '14

#8447: A combination of type-level comparison and subtraction does not work for 0 -------------------------------------+------------------------------------- Reporter: nushio | Owner: Type: bug | Status: new Priority: low | Milestone: Component: Compiler (Type | Version: 7.6.3 checker) | Operating System: Linux Keywords: | Type of failure: GHC rejects Architecture: Unknown/Multiple | valid program Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | -------------------------------------+------------------------------------- The following function on type level naturals {{{ Diff x y = If (x <=? y) (y-x) (x-y) }}} does not work when either x or y is 0. https://github.com/nushio3/practice/blob/ea8a1716b1d6221ce32d77432b6de3f38e… /type-nats/int-bug.hs I've tested this code on ghc 7.7.20130926 since I couldn't build the really latest ghc. I'm sorry if it is already fixed on the ghc head. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8447> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 5

[GHC] #8442: Cabal-install internal error with any use
by GHC 18 Nov '14

18 Nov '14

#8442: Cabal-install internal error with any use ----------------------------------+--------------------------------- Reporter: senk | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Package system | Version: 7.6.3 Keywords: | Operating System: FreeBSD Architecture: x86_64 (amd64) | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+--------------------------------- Any attempt to use cabal-install fails with an internal error. Used FreeBSD (9.1) port hs-haskell-platform and built with hs-colour support, LLVM (3.2) backend, and profiling enabled. Warnings were given that the version of LLVM used was untested, but no issues were apparent when compiling. {{{ cabal install hakyll cabal-install: internal error: evacuate(static): strange closure type -385875968 (GHC version 7.6.3 for x86_64_portbld_freebsd) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug Abort trap }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8442> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 3

[GHC] #8465: ./configure fails on ghc-7.6.3: does not find installed libgmp.so.3 and current directory
by GHC 18 Nov '14

18 Nov '14

#8465: ./configure fails on ghc-7.6.3: does not find installed libgmp.so.3 and current directory ------------------------------------+------------------------------------- Reporter: ygramoel | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Build System | Version: 7.6.3 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------------- I am trying to reproduce bug #8464 with the newest ghc; not available in my repositories, so I am trying to install it manually. With a freshly downloaded and unpacked ghc-7.6.3-x86_64-unknown- linux.tar.bz2, and after cleanly installing libgmp.3 (from source of gmp-4.3.1) johan@morla:~/work/ghc-7.6.3\> ./configure checking for path to top of build tree... utils/ghc-pwd/dist- install/build/tmp/ghc-pwd: error while loading shared libraries: libgmp.so.3: cannot open shared object file: No such file or directory configure: error: cannot determine current directory johan@morla:~/work/ghc-7.6.3\> pwd -P /home/johan/work/ghc-7.6.3 johan@morla:~/work/ghc-7.6.3\> whereis libgmp libgmp: /usr/local/lib/libgmp.la /usr/local/lib/libgmp.a /usr/local/lib/libgmp.so johan@morla:~/work/ghc-7.6.3\> ls -l /usr/local/lib/libgmp* -rw-r--r-- 1 root root 1017334 Oct 20 20:56 /usr/local/lib/libgmp.a -rwxr-xr-x 1 root root 785 Oct 20 20:56 /usr/local/lib/libgmp.la lrwxrwxrwx 1 root root 15 Oct 20 20:56 /usr/local/lib/libgmp.so -> libgmp.so.3.5.0 lrwxrwxrwx 1 root root 15 Oct 20 20:56 /usr/local/lib/libgmp.so.3 -> libgmp.so.3.5.0 -rwxr-xr-x 1 root root 403890 Oct 20 20:56 /usr/local/lib/libgmp.so.3.5.0 johan@morla:~/work/ghc-7.6.3\> -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8465> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 2

[GHC] #8477: Allow inferring ambiguous types
by GHC 18 Nov '14

18 Nov '14

#8477: Allow inferring ambiguous types ------------------------------------+------------------------------------- Reporter: aavogt | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: 8390 | ------------------------------------+------------------------------------- Previous versions of ghc could infer types that are potentially ambiguous. This allowed things like http://okmij.org/ftp/Haskell/TypeLambdaVal.hs or assigning keyword args functions to variables http://code.haskell.org/~aavogt/HList/docs/HList/Data-HList-Keyword.html. Presently (7.6 and 7.7), you need to write a type signature yourself to allow such definitions, which in these situations doubles the amount of code to write. For the keyword case, the workaround is to use the kw function to apply the keyword function instead of ordinary function application. More related discussion http://www.haskell.org/pipermail/glasgow-haskell- users/2013-October/024404.html -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8477> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 7

[GHC] #8490: OS X 10.9 gcc-4.8 unknown symbol `__objc_empty_table`
by GHC 18 Nov '14

18 Nov '14

#8490: OS X 10.9 gcc-4.8 unknown symbol `__objc_empty_table` ----------------------------------+--------------------------------------- Reporter: jloos | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Keywords: | Operating System: MacOS X Architecture: x86_64 (amd64) | Type of failure: Compile-time crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+--------------------------------------- I'm not sure if and how far the ghc-7.6.3 support for OS X is planned, but I hit a (possible) linker error with 7.6.3. I installed a homebrew gcc-4.8 and changed the ghc config to use it. I tried to compile the [http://hackage.haskell.org/package/bindings-GLFW bindings-GLFW] package, which was successful, and run `cabal test` on it, which fails with following error: {{{ final link ... ghc: lookupSymbol failed in relocateSection (relocate external) dist/build/HSbindings-GLFW-3.0.3.o: unknown symbol `__objc_empty_vtable' linking extra libraries/objects failed }}} After some research I discovered that this symbol (surely just the first which fails) is part of the Objective-C Runtime. The /usr/lib/libobjc.dylib exports this symbol. In desperation I think I nearly reached the google quota with my research, further steps I tried: Explicitly link the libobjc lib {{{ ghci -lobjc dist/build/HSbindings-GLFW-3.0.3.o -framework Foundation -framework Cocoa -framework IOKit }}} With the same result as above: {{{ GHCi, version 7.6.3: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading object (static) dist/build/HSbindings-GLFW-3.0.3.o ... done Loading object (dynamic) /usr/lib/libobjc.dylib ... done Loading object (framework) IOKit ... done Loading object (framework) Cocoa ... done Loading object (framework) Foundation ... done final link ... ghc: lookupSymbol failed in relocateSection (relocate external) dist/build/HSbindings-GLFW-3.0.3.o: unknown symbol `__objc_empty_vtable' linking extra libraries/objects failed }}} I found a [https://github.com/mxcl/homebrew/issues/23687 homebrew issue] related to gcc and the Apple switch from libstdc++to libc++ in 10.9 and i tried to force linking with explicit `-stdlib=libstdc++` in the cabal file (ld-options). But i guess this issue isn't related to the `__objc_***` problem, just tried it in desperation. Last week I managed to build ghc HEAD with clang bootstrapped with 7.4.6: the new linker mechanic seems to resolves this problem in a way (sadly some other packages aren't jet compatible with 7.8) So I'm not sure if this report is okay, if not, pardon me :) I'm aware of the problems with the current ghc-7.6.3 and the the changes OS X 10.9 brings with it (according to reddit/haskell cafe). The current suggestions is to not use the XCode-5.0.1/clang together with ghc-7.6.3. So I tried gcc from homebrew. I know that 7.8 will bring better linker capabilities, maybe there are just some flags to fix this specific problem with 7.6.3...? I didn't find it. So I thought it's better to report it. If further informations are required, I will try to provide them as fast as possible but I will have to downgrade to 10.8 tomorrow around 6 a.m. UTC. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8490> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 3

[GHC] #9391: LLVM 3.2 crash (AVX messes up GHC calling convention)
by GHC 18 Nov '14

18 Nov '14

#9391: LLVM 3.2 crash (AVX messes up GHC calling convention) -------------------------------------+------------------------------------- Reporter: scpmw | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (LLVM) | Version: 7.8.2 Keywords: | Operating System: MacOS X Architecture: Unknown/Multiple | Type of failure: Runtime Difficulty: Easy (less than 1 | crash hour) | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- I stumbled across the problem of LLVM 3.2 builds seemingly randomly crashing on my Mac. After quite a bit of investigation I found that the source of the problem was somewhere in the `base` library (`span` to be precise), where it encountered Cmm like follows: {{{ cp7n: if ((Sp + -56) < SpLim) goto cp8c; else goto cp8d; ... cp8d: I64[Sp - 40] = block_cp7g_info; _smKL::P64 = P64[R1 + 7]; _smKO::P64 = P64[R1 + 15]; _smKP::P64 = P64[R1 + 23]; _smL0::P64 = P64[R1 + 31]; R1 = R2; P64[Sp - 32] = _smKL::P64; P64[Sp - 24] = _smKO::P64; P64[Sp - 16] = _smKP::P64; P64[Sp - 8] = _smL0::P64; Sp = Sp - 40; if (R1 & 7 != 0) goto up8R; else goto cp7h; up8R: call block_cp7g_info(R1) args: 0, res: 0, upd: 0; ... }}} which leads LLVM 3.2 to produce the following assembly: {{{ _smL1_info: ## @smL1_info ## BB#0: ## %cp7n pushq %rbp movq %rsp, %rbp movq %r14, %rax movq %rbp, %rcx leaq -56(%rcx), %rdx cmpq %r15, %rdx jae LBB160_1 ... LBB160_1: ## %cp8d leaq _cp7g_info(%rip), %rdx movq %rdx, -40(%rcx) vmovups 7(%rbx), %ymm0 vmovups %ymm0, -32(%rcx) addq $-40, %rcx testb $7, %al je LBB160_4 ## BB#2: ## %up8R movq %rcx, %rbp movq %rax, %rbx popq %rbp vzeroupper jmp _cp7g_info ## TAILCALL }}} So here LLVM has figured out that it can use `vmovups` in order to move 4 words at the same time. However, there is a puzzling side effect: All of sudden we have a `pushq %rbp` at the start of the function with a matching `popq %rbp` at the very end. This overwrites the stack pointer update (`movq %rcx, %rbp`) and - unsurprisingly - causes the program to crash rather quickly. My interpretation is that LLVM 3.2 erroneously thinks that AVX instructions are incompatible with frame pointer elimination. The reasoning is that this is exactly the kind of code LLVM generates if we disable this "optimisation" (`--disable-fp-elim`). Furthermore, disabling AVX instructions (`-mattr=-avx`) fixes the problem - LLVM falls back to the less efficient `movups`, with `pushq $rbp` vanishing as well. Finally, this bug seems to happen exactly with LLVM 3.2, with 3.3 upwards generating correct code. My proposed fix would be to add `-mattr=-avx` to the `llc` command line by default for LLVM 3.2. This issue might be related to #7694. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9391> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 7

[GHC] #9185: glibc 2.20 outputs warnings for _BSD_SOURCE (Stg.h) on unknowns archs
by GHC 18 Nov '14

18 Nov '14

#9185: glibc 2.20 outputs warnings for _BSD_SOURCE (Stg.h) on unknowns archs -------------------------+------------------------------------------------- Reporter: | Owner: juhpetersen | Status: new Type: bug | Milestone: Priority: | Version: 7.8.2 normal | Operating System: Linux Component: | Type of failure: Incorrect warning at Compiler | compile-time Keywords: | Test Case: Architecture: | Blocking: Unknown/Multiple | Difficulty: | Unknown | Blocked By: | Related Tickets: | -------------------------+------------------------------------------------- Stg.h defines _BSD_SOURCE which glibc 2.20 deprecates with warnings in favour of _DEFAULT_SOURCE. Since the verbose warning is output for every ghc invocation when building it is rather annoying and induces testsuite failures. The warning look like this: {{{ In file included from /usr/include/math.h:26:0: 0, from /usr/lib64/ghc-7.6.3/include/Stg.h:65, from /tmp/ghc783_0/ghc783_0.hc:3: /usr/include/features.h:148:3: warning: #warning "_BSD_SOURCE and _SVID_SOURCE are deprecated, use _DEFAULT_SOURCE" [-Wcpp] # warning "_BSD_SOURCE and _SVID_SOURCE are deprecated, use _DEFAULT_SOURCE" ^ }}} Solution/workaround is to define "_DEFAULT_SOURCE" and that works. I asked in https://bugzilla.redhat.com/show_bug.cgi?id=1067110#c13 about how best to fix Stg.h and got the answer to just add _DEFAULT_SOURCE. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9185> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #9578: Quoting issue in configure.ac
by GHC 18 Nov '14

18 Nov '14

#9578: Quoting issue in configure.ac -------------------------------------+------------------------------------- Reporter: gintas | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Build System | Version: 7.9 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Easy (less than 1 | Type of failure: Building hour) | GHC failed Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Some ghc invocations in configure.ac are not properly quoted, causing ./configure to spew errors if there are spaces in the path. See attached patch. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9578> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 2