Building the GHC library without building GHC

Hi, I was going to do some hacking on Haddock.  Haddock depends on the GHC API from the development version of GHC, however, stage2 crashes on my system when I try to build the newest GHC from the repository.  Since I don't actually need to compile with the new GHC, I'm hoping there's a workar

Global constant propagation

I'm curious about global constant propagation in GHC.  It's a fairly basic optimization in the CFG-based compiler domain, and it's similar to constructor specialization, but it doesn't seem to be in GHC's repertoire.  Perhaps it's usually subsumed by other optimizations or it's more complicated

RE: Elimination of absurd patterns

s 'fooName' does not. > Date: Mon, 2 May 2011 23:03:23 -0300 > Subject: Re: Elimination of absurd patterns > From: felipe.le...@gmail.com > To: red...@hotmail.com > CC: glasgow-haskell-users@haskell.org > > On Mon, May 2, 2011 at 6

Elimination of absurd patterns (reformatted)

I'm re-sending this e-mail, hopefully with proper line breaks this time. I was experimenting with using GADTs for subtyping when I found something interesting.  Hopefully someone can satisfy my curiosity. Here are two equivalent GADTs.  My understanding was that GHC would translate "Foo" and "

Elimination of absurd patterns

I was experimenting with using GADTs for subtyping when I found something interesting. Hopefully someone can satisfy my curiosity. Here are two equivalent GADTs. My understanding was that GHC would translate "Foo" and "Bar" into isomorphic data types. However, GHC 6.12.3 generates better cod

Meaning of ghc-pkg package-conf flags

Hello, I'd like to know how ghc-pkg searches package databases and how the command-line flags affect the search. My model of ghc-pkg was that it builds a list of package databases and then searches them starting from the head. I'd like to work with a sandboxed local package database. Lookin

Re: Equality constraint type mismatch

(Hotmail is again swallowing newlines--sorry for the re-post) I see.  The type inference algorithm requires type variables to be type constructors, not functions.  Equality constraints are simplified assuming that is the case.  I knew that type functions had to be fully applied, but I didn't know

Re: Equality constraint type mismatch

I see. The type inference algorithm requires type variables to betype constructors, not functions. Equality constraints aresimplified assuming that is the case. I knew that typefunctions had to be fully applied, but I didn't know that they alsocouldn't be "taken apart" by unification. This

Equality constraint type mismatch

I would like help understanding a type error I'm getting with GHC 6.10.4. GHC reports a type mismatch for the types in a satisfiable equality constraint.  The function "idLazy" below demonstrates the error.  I would appreciate if someone can explain what's going on. Thanks, -heatsink {-# LANGUAG

Type checker's expected and inferred types (reformatted)

> Which message do you prefer? I couldn't tell which it was. I prefer fun1.  In my understanding, the 'inferred' type is gleaned by looking at theexpression itself, while the 'expected' type is implied by the context. ___

Type checker's expected and inferred types (reformatted)

(Some formatting was apparently lost en route.  Trying again with extra newlines.) I came across a type error that misled me for quite a while, because the expected and inferred types were backwards (from my point of view).  A simplified example is below.  Can someone explain how GHC's type che

Type checker's expected and inferred types

I came across a type error that misled me for quite a while, because the expected and inferred types were backwards (from my point of view). A simplified example is below. Can someone explain how GHC's type checker creates the error message? In this example, fun1 and fun2 are basically the s

Re: Ghci dynamic linking (Was: C++ libraries and GHCI)

I've encountered the problem with weak symbols also, and filed a bug report against ghc (#). Weak symbols are used by gcc (with elf) to accommodate C++'s compilation model. In C++, it's permitted to define class methods and template code in header files. Because header files can be includ

RE: Type classes in GADTs

Thanks for the explanation. I see how this wouldn't behave nicely with automatic class constraint inference. I didn't test the example on any other GHC versions. I will probably end up passing in the Eq dictionary from outside like Daniil suggested. I would prefer to do the following, but G

Type classes in GADTs

I discovered that closed type classes can be implicitly defined using GADTs. The GADT value itself acts like a class dictionary. However, GHC (6.8.3) doesn't know anything about these type classes, and it won't infer any class memberships. In the example below, an instance of Eq is not recog

Re: SHA1.hs woes, was Version control systems

I've "fixed" this problem by increasing the number of registers used on ia64 to 34. The problem will show up again if anyone finds a way to make GCC use even more registers. -heatsink >> >> Sorry, I couldn't find the rest of the preceding message. Someone >> wrote that they had to turn dow

RE: Login problems with trac

The wiki has "edit" links if I login as guest, but not if I login as heatsink. Is that also because of the spam issue? _ Get a FREE Web site, company branded e-mail and more from Microsoft Office Live! http://clk.atdmt.com/MRT/go/