instance Read Integer/Rational/Double readsPrec out of memory and crash due to exponential notation
GHCi, version 6.12.3: http://www.haskell.org/ghc/ Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Loading package ffi-1.0 ... linking ... done. 120000000000 Prelude> read "12e1000000000000" :: Integer Segmentation fault
Sometimes it fails with Bus error.
According to Haskell'98 and Haskell'00 Reports Integers should not parse exponential notation at all.
This is security issue in web frameworks as parsing HTTP headers, URLs, JSON and other may involve parsing integers.