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.
http://www.haskell.org/onlinereport/haskell2010/haskellch2.html\#x7-190002.5
This is security issue in web frameworks as parsing HTTP headers, URLs, JSON and other may involve parsing integers.