Documentation bug: list of builtin functions

[Niels Möller]

The list of builtin functions in the node "C Dialect options" seems
to be incorrect:

  `-fno-builtin'
       Don't recognize builtin functions that do not begin with
       `__builtin_' as prefix.  Currently, the functions affected include
       `abort', `abs', `alloca', `cos', `exit', `fabs', `ffs', `labs',
       `memcmp', `memcpy', `sin', `sqrt', `strcmp', `strcpy', and
       `strlen'.

For instance, memset seems to be a builtin:

  $ echo "int memset(int);" | gcc -x c - -c -o /dev/null
  :1: warning: conflicting types for built-in function `memset'

/Niels