Squished the bug that prevents this branch from generating code that
runs properly: I overlooked the #defines in libc.h which are treated by
the compiler as text, not as C integers, so that
integer indices emitted in the generated SABR code for calling into
LIBC were in decimal but were then interpreted by SABR as octal.  If this gave syntactically correct code, it would call the wrong
function for every function past index 7.  The fact that we never saw it
generate syntactically incorrect code merely reflects the fact that we
didn't happen to call any functions that used decimal indexes that have
no corresponding octal interpretation, a possibility only 1/5 of the time.  (e.g. 29)