[BuildTools] Problem with ASL and AC_CHECK_SIZEOF(long long)

[Kipp Martin]

Hi:

If you 1) build a project that uses ASL and 2) use configure with -C, 
then if you later try to use

AC_CHECK_SIZEOF(long long)

you get the error

checking size of long long... configure: error: cannot compute sizeof 
(long long), 77
See `config.log' for more details.
configure: error: /bin/sh '../../COIN-OS/OS/configure' failed for OS
kmartin-maclt:~/Documents/files/code/cpp/OScpp/vpath kmartin$

the problem is that in ASL there is

  AC_CHECK_TYPE([long long],[],
       [asladdcflags="$asladdcflags -DNO_LONG_LONG"],[])

and this is calculated for C which which gives a value of

ac_cv_sizeof_long_long=8,

however in C++ it is 0.  This causes all sorts of problems if someone 
configures your project with -C because cached values are used when you 
later try to find the size of long long using AC_CHECK_SIZEOF(long long).

When trying to find the value of variable, is there a way to tell 
autoconf to ignore the cached variables?

Thanks


-- 
Kipp Martin
Professor of Operations Research
and Computing Technology
Graduate School of Business
University of Chicago
5807 South Woodlawn Avenue
Chicago, IL 60637
773-702-7456
kipp.martin at chicagogsb.edu
http://gsbkip.chicagogsb.edu
http://www.coin-or.org