On Tue, Apr 16, 2013 at 11:36:20PM +0100, David Laight wrote: > On Tue, Apr 16, 2013 at 07:34:58PM +0000, Joerg Sonnenberger wrote: > > Module Name: src > > Committed By: joerg > > Date: Tue Apr 16 19:34:58 UTC 2013 > > > > Modified Files: > > src/common/lib/libc/stdlib: _strtol.h _strtoul.h > > > > Log Message: > > Do not use isalpha here, since we explicitly only support the Portable > > Character Set as base and in theory a locale could define a ASCII > > control character as letter, resulting in negations. Also avoid isdigit > > here to give the compiler a better chance of deciding whether an > > unsigned compare or a jump table is a better option, both are very > > likely better choices than the memory indirection. > > There really ought to be a way of requesting the straight ASCII > versions of the isxxxx functions even after a local has been set. > A lot of code will use isalpha() to check for valid variable names (etc) > and really doesn't want locale-specific alpha characters be valid. > (Otherwise scripts become non-portable.)
See the discussion about using loc==0. > OTOH (unsigned)(ch - '0') <= 9 is probably the fastest isdigit() > on any modern cpu. I expect the compiler to do that transformation. Joerg
