Literal overflow test fails

Simon Peyton-Jones simonpj at
Sat Aug 3 23:47:07 CEST 2013

On 32 bit Windows I get this (with HEAD).

libraries\Win32\Graphics\Win32\GDI\HDC.hs:145:14: Warning:
    Literal 2147483648 of type Int overflows

The offending code is:

setTextCharacterExtra dc extra =
  failIf (== 0x80000000) "SetTextCharacterExtra" $
    c_SetTextCharacterExtra dc extra

The new literal-overflow test objects to 0x80000000 :: Int.  I'm not sure if it should object; in this case we are deliberately using the bit-pattern for minBound.

Also what happens on a 64-bit architecture?

What should the behaviour here be?

- should we use minBound here?
- what should the new literal-overlflow code do for 0xblah constants?

This is currently breaking the HEAD build.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the ghc-devs mailing list