November 2014 - ghc-tickets

[GHC] #8309: traceEvent truncates to 512 bytes
by GHC 23 Feb '15

23 Feb '15

#8309: traceEvent truncates to 512 bytes ------------------------------------+------------------------------------- Reporter: duncan | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Runtime System | Version: 7.6.3 Keywords: eventlog tracing | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------------- The `Debug.Trace.traceEvent` (& `traceEventIO`) use a code path that unnecessarily uses printf format strings and uses a fixed size 512-byte buffer, hence truncating all user trace messages at that size. Here is the call path: * `Debug.Trace.traceEvent` (& `traceEventIO`) call `traceEvent#` primop * cmm impl of the primop `stg_traceEventzh` calls C RTS function `traceUserMsg` * `traceUserMsg` calls `traceFormatUserMsg(cap, "%s", msg);`, using the printf format string * `traceFormatUserMsg` uses `postUserMsg` which eventually calls `postLogMsg` * `postLogMsg` does the printf stuff Here's what `postLogMsg` does: {{{ #define BUF 512 void postLogMsg(EventsBuf *eb, EventTypeNum type, char *msg, va_list ap) { char buf[BUF]; nat size; size = vsnprintf(buf,BUF,msg,ap); if (size > BUF) { buf[BUF-1] = '\0'; size = BUF; } .... }}} This is obviously designed for RTS-internal users, not the user path. So the problem starts with this bit: {{{ void traceUserMsg(Capability *cap, char *msg) { traceFormatUserMsg(cap, "%s", msg); } }}} It just should not use that code path. It should call something that directly posts the message, without any silly printf strings. In fact, the code path from the primop down should really be changed to use an explicit given length, rather than using a null-terminated string and having to call strlen. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8309> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 5

[GHC] #8546: Panic during cabal build with profiling enabled.
by GHC 23 Feb '15

23 Feb '15

#8546: Panic during cabal build with profiling enabled. ---------------------------------+--------------------------------------- Reporter: Mokosha | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Keywords: cabal sandbox | Operating System: Windows Architecture: x86 | Type of failure: Compile-time crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ---------------------------------+--------------------------------------- I had been recently using cabal-dev for my development work. Someone suggested I switch over to the new cabal 1.18 on #haskell. After doing so, some projects do not seem to build anymore. I'm not an experienced Haskell developer, so I'm not sure how to go about debugging such a problem. I've included the output of the install command. {{{ Pavel@ZOMBIE-POWER ~/Projects/Lambency/src $ cabal install -p Resolving dependencies... Configuring bindings-GLFW-3.0.3.1... Building bindings-GLFW-3.0.3.1... Preprocessing library bindings-GLFW-3.0.3.1... [1 of 1] Compiling Bindings.GLFW ( dist\dist-sandbox- 2b66993e\build\Bindings\GLFW.hs, dist\dist-sandbox- 2b66993e\build\Bindings\GLFW.o ) [1 of 1] Compiling Bindings.GLFW ( dist\dist-sandbox- 2b66993e\build\Bindings\GLFW.hs, dist\dist-sandbox- 2b66993e\build\Bindings\GLFW.p_o ) In-place registering bindings-GLFW-3.0.3.1... Installing library in D:\MinGW\msys\1.0\home\Pavel\Projects\Lambency\build\i386-windows- ghc-7.6.3\bindings-GLFW-3.0.3.1 Registering bindings-GLFW-3.0.3.1... Installed bindings-GLFW-3.0.3.1 Configuring GLFW-b-1.4.1... Building GLFW-b-1.4.1... Preprocessing library GLFW-b-1.4.1... [1 of 3] Compiling Graphics.UI.GLFW.Types ( Graphics\UI\GLFW\Types.hs, dist\dist-sandbox-2b66993e\build\Graphics\UI\GLFW\Types.o ) Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading package bindings-DSL-1.0.20 ... linking ... done. Loading package bindings-GLFW-3.0.3.1 ... ghc.exe: Unknown PEi386 section name `.drectve' (while processing: D:\MinGW\msys\1.0\home\Pavel\Projects\Lambency\build\i386-windows- ghc-7.6.3\bindings-GLFW-3 .0.3.1\libHSbindings-GLFW-3.0.3.1.a) ghc.exe: panic! (the 'impossible' happened) (GHC version 7.6.3 for i386-unknown-mingw32): loadArchive "D:\\MinGW\\msys\\1.0\\home\\Pavel\\Projects\\Lambency\\build\\i386 -windows-ghc-7.6.3\\bindings-GLFW-3.0.3.1\\libHSbindings-GLFW-3.0.3.1.a": failed Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug Failed to install GLFW-b-1.4.1 cabal.exe: Error: some packages failed to install: GLFW-b-1.4.1 failed during the building phase. The exception was: ExitFailure 1 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8546> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #9664: Add identity functor to base
by GHC 22 Feb '15

22 Feb '15

#9664: Add identity functor to base -------------------------------------+------------------------------------- Reporter: hvr | Owner: ekmett Type: task | Status: new Priority: normal | Milestone: 7.10.1 Component: Core Libraries | Version: Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Easy (less than 1 | Type of failure: hour) | None/Unknown Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- `base` already provides a `Const`ant functor, but the even more useful `Id`entity (or `Identity`) functor does not exist in `base` yet. This was already [https://groups.google.com/forum/#!msg/haskell-core- libraries/_nReDCbROew/Mdmf0zIloysJ proposed to the CLC back in early 2013], and already missed inclusion in GHC 7.8 However, in order to implement this, coordination with `transformers` is desirable, as `transformers` currently provides a non-transforming `Data.Functor.Identity`, and we'd like to avoid name clashes. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9664> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 13

[GHC] #9631: Comment in GHC.Base about GHC.Prim does not appear to be correct
by GHC 22 Feb '15

22 Feb '15

#9631: Comment in GHC.Base about GHC.Prim does not appear to be correct -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: libraries/base | Version: 7.8.3 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | Documentation bug Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- The comment reads {{{ GHC.Prim Has no implementation. It defines built-in things, and by importing it you bring them into scope. The source file is GHC.Prim.hi-boot, which is just copied to make GHC.Prim.hi }}} It does not appear that any files by these names exist. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9631> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 2

[GHC] #8362: Filesystem related tests failed on solaris (SmartOS)
by GHC 22 Feb '15

22 Feb '15

#8362: Filesystem related tests failed on solaris (SmartOS) --------------------------+------------------------------------------------ Reporter: leroux | Owner: Type: bug | Status: new Priority: high | Milestone: 7.8.1 Component: | Version: 7.6.3 libraries (other) | Operating System: Solaris Keywords: | Type of failure: Incorrect result at runtime Architecture: | Test Case: Unknown/Multiple | Blocking: Difficulty: | Unknown | Blocked By: | Related Tickets: | --------------------------+------------------------------------------------ Getting filesystem (files/permissions) related test faiures on SmartOS (32bit). {{{ $ uname -a SunOS pkgx86 5.11 joyent_20130919T215407Z i86pc i386 i86pc Solaris }}} Unexpected failures: `TEST="openFile003 getPermissions001 processGroup002 user001 posix005"` The testsuite output is attached. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8362> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #9388: Narrow the scope of the notorious "state hack"
by GHC 22 Feb '15

22 Feb '15

#9388: Narrow the scope of the notorious "state hack" -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- The "state hack" has caused any number of bug reports (just search for that string), the most recent of which is #9349. Here's an idea to make it less pervasive: (roughly) use the state hack only for top-level functions definitions. The idea is that for nested lambdas the context should give the one-shot- ness, now that we are equipped with cardinality analysis. For example, consider the call {{{ replicatM_ 1000 (\(s :: RealWorld#) -> blah) }}} The lambda is 1000-shot, not one-shot, notwithstanding the type of the binder. Moreover `replicateM_`'s strictness/cardinality signature will say just that, and GHC already knows how to propagate that information onto the `\s`. But for top level functions like {{{ pr :: String -> IO () pr x = putStrLn (reverse x) }}} we get Core {{{ pr = \x. let y = reverse x in \ (s :: State# RealWorld). putStrLn y s }}} and, since we can't see all the callers of `pr`, we don't know if work is lost by pushing the `reverse` call inside, to get {{{ pr = \x. (s :: State# RealWorld). putStrLn (reverse x) s }}} which is much more efficient. Indeed, this might not be so good if the calls looked like {{{ ... replicateM_ 1000 (pr "foo")... }}} because then "foo" will be reversed 1000 times. But arguably that's what the programmer expects anyway, looking at the code; and the efficiency hit from not eta-expanding all functions like `pr` (which are very very common) is significant. The point is the that the only ones that need hacking are the top-level guys, and maybe even the top-level ''exported'' guys. I have not fully thought this through, let alone tried it out, but I wanted to capture the thought. It would need some careful performance testing. Simon -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9388> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 6

[GHC] #8280: Deriving Show for Word#
by GHC 21 Feb '15

21 Feb '15

#8280: Deriving Show for Word# ------------------------------------+------------------------------------- Reporter: monoidal | Owner: Type: bug | 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: | ------------------------------------+------------------------------------- {{{ {-# LANGUAGE MagicHash #-} import GHC.Prim data A = A Word# deriving Show }}} This works in 7.6.3, but 7.7 gives {{{ Can't find interface-file declaration for data constructor GHC.Types.W# Probable cause: bug in .hi-boot file, or inconsistent .hi file Use -ddump-if-trace to get an idea of which file caused the error }}} The same file works if Word# is replaced by Int#. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8280> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 9

[GHC] #9054: runghc-<version> does not call ghc of the same version
by GHC 18 Feb '15

18 Feb '15

#9054: runghc-<version> does not call ghc of the same version ------------------------------------+------------------------------------- Reporter: EyalLotem | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------------- When I ran runghc-7.6.3, it actually executed "/usr/local/bin/ghc" which points to ghc-7.8.2. The offending line is inside the runghc-<version> script: {{{ exec "$executablename" -f "$bindir/ghc" ${1+"$@"} }}} Which should be: {{{ exec "$executablename" -f "$bindir/ghc-<version>" ${1+"$@"} }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9054> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 3

[GHC] #9402: Vestigial external core code in genprimops
by GHC 18 Feb '15

18 Feb '15

#9402: Vestigial external core code in genprimops -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.9 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- It looks like `gen_ext_core_source` in `utils/genprimopcode/Main.hs` is no longer needed. I'm not quite confident enough here to make the change myself, though. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9402> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #9606: Improve outdated ghc-pkg cache warning
by GHC 18 Feb '15

18 Feb '15

#9606: Improve outdated ghc-pkg cache warning -------------------------------------+------------------------------------- Reporter: nh2 | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.10.1 Component: ghc-pkg | Version: 7.8.2 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Easy (less than 1 | Type of failure: hour) | None/Unknown Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Sometimes you get this: {{{ WARNING: cache is out of date: /home/user/.ghc/x86_64-linux-7.8.3/package.conf.d/package.cache. Use 'ghc-pkg recache' to fix }}} The warning is correct but a bit confusing, because running `ghc-pkg recache` does nothing here: It will by default update your global package DB, and the DB the warning is about will still be out of date. This seems to have frustrated others as well: https://gist.github.com/mcandre/5789498 I suggest we make the message more clear: `You might have to pass --user to update this cache file`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9606> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4