ross 2004/09/30 09:49:07 PDT Modified files: src builtin.h dirprim.c iomonad.c timeprim.c Log: Fix for bug reported by Henk-Jan van Tuyl, in which the following corrupts the heap if "foo" isn't found: import System.IO main :: IO () main = do h1 <- openFile "/usr/dict/words" ReadMode let fileName = "foo" h2 <- openFile fileName ReadMode return () The second openFile triggers a GC, which corrupts the indirection to fileName used by the error report. The bug has been there a long time, but has emerged now because we cut the starting size of the handle table (to make rare bugs more common). Today I learned that Cell x = ...; <possible GC> ... x ... is unsafe if x could refer to an indirection, even with conservative GC, even if there are copies of x on the stack. The fix is ugly (use a Cell * instead) but I couldn't think of anything better. Revision Changes Path 1.7 +3 -3 hugs98/src/builtin.h 1.19 +76 -76 hugs98/src/dirprim.c 1.80 +130 -130 hugs98/src/iomonad.c 1.12 +16 -16 hugs98/src/timeprim.c