Technical Q for a `build from source' adept

[Harry Putnam <reader@newsguy.com>]

I'm trying to build a package on another OS, so this may be a bit OT
but it really more of a general `developer' kind of question.

A package (xbindkeys) goes through the `./configure' phase ok, seeming
to find every thing it needs.

But `make' breaks out pretty early on:

,----
| make  all-am
| make[1]: Entering directory `/usr/local/src/xbindkeys-1.8.5'
| gcc -DHAVE_CONFIG_H -I.    -g -O2  -DFORK_FLAG=1 -DGUILE_FLAG=1  -I/usr/include/gmp -D_REENTRANT -pthreads -I. -Wall -g -O2 -MT xbindkeys.o -MD -MP -MF .deps/xbindkeys.Tpo -c -o xbindkeys.o xbindkeys.c
| In file included from /usr/include/libguile.h:67,
|                  from keys.h:23,
|                  from xbindkeys.c:30:
| /usr/include/libguile/numbers.h:31:28: floatingpoint.h: No such file or directory
| xbindkeys.c: In function `catch_CHLD_signal':
| xbindkeys.c:498: warning: int format, pid_t arg (arg 2)
| make[1]: *** [xbindkeys.o] Error 1
| make[1]: Leaving directory `/usr/local/src/xbindkeys-1.8.5'
| make: *** [all] Error 2
`----

I'm not good enough at reading this kind of stuff to be able to tell
what the actual error is.

Is it the missing file `floatingpoint.h', or something found at line
498 in xbindkeys.c?

I did check the referenced line numbers in floatingpoint.h:31:28:
   [...]
25 #include <gmp.h>

27 #include "libguile/__scm.h"
28 #include "libguile/print.h"

30 #if SCM_HAVE_FLOATINGPOINT_H
31 # include <floatingpoint.h>
32 #endif

34 #if SCM_HAVE_IEEEFP_H
35 # include <ieeefp.h>
36 #endif
  [...]

I notice some file names are enclosed in double quotes and some in
brackets (<>).  What is the significance of quotes, and of brackets?