I think we want machine pattern i.86 not i386 --- looks like config.guess

could output several different high digits on most PC Unixen.

src/test/regress/resultmap

@@ -4,7 +4,7 @@ abstime/sparc-sun-solaris=abstime-solaris-1947
 float4/.*-qnx=float4-exp-three-digits
 float8/.*-bsdi=float8-small-is-zero
 float8/.*-freebsd*=float8-small-is-zero
-float8/i386-.*-netbsd=float8-small-is-zero
+float8/i.86-.*-netbsd=float8-small-is-zero
 float8/.*-qnx=float8-exp-three-digits
 float8/alpha.*-dec-osf=float8-fp-exception
 float8/i.86-pc-cygwin*=float8-cygwin