If you want the over-engineered version in glibc, then build your Perl with d_strtod=1

Another way to get glibc to assign the value is to use POSIX::strtod.
Unlike my perl-5.22.0, it correctly assigns '-4.848e1':

C:\>perl -MPOSIX="strtod" -le "print scalar reverse unpack 'h*', pack 
+'d<',strtod('-4.848e1');"
c0483d70a3d70a3d
[download]

In my experience, glibc gets the assignment right for those values that perl gets wrong - though not so much with the non-IEEE "double-double" arrangement, where both are prone to error.
However, I shouldn't assert that perl is any worse at assigning values than glibc. (I don't know how often glibc gets it wrong when perl gets it right.)

Cheers,
Rob