Opened 9 years ago

Closed 9 years ago

#897 closed bug (fixed)

Missing instance declaration on Mac OS X (PPC)

Reported by: edsko@… Owned by:
Priority: normal Milestone:
Component: Compiler Version: 6.4.2
Keywords: Cc:
Operating System: MacOS X Architecture: powerpc
Type of failure: Test Case:
Blocked By: Blocking:
Related Tickets: Differential Rev(s):
Wiki Page:


When compiling ghc 6.4.2 on Mac OS X (Darwin), configured as

./configure --disable-openal --disable-alut

(with GNU readline installed), and the settings as suggested in HACKING, compilation fails with the following error:


No instance for (Show FreeRegs)

arising from use of `show' at nativeGen/RegisterAlloc.hs:639:146-149

Probable fix: add an instance declaration for (Show FreeRegs) In the first argument of text', namely (show freeregs)' In the first argument of (<+>)', namely text (show freeregs)' In the first argument of (<+>)', namely (text (show freeregs)) <+> (ppr r)

This error disappears when -DDEBUG is removed from the compilation errors.

Change History (1)

comment:1 Changed 9 years ago by simonpj

  • Resolution set to fixed
  • Status changed from new to closed

Fixed in the HEAD (deriving Show for FreeRegs)

Note: See TracTickets for help on using tickets.