[Help-glpk] bug detected in cplex lp format parsing routine

[Andrew Makhorin]

A bug was detected in the cplex lp format parsing routine (glpk 4.7),
due to which the keyword 'minimize' or 'maximize' appearing on the very
first line is not recognized.

To fix the bug please just remove lines 825 and 826 in glplpx8c.c, i.e.
replace the fragment:

823:       dsa->lp = lpx_create_prob();
824:       lpx_create_index(dsa->lp);
825:       /* read very first character */
826:       read_char(dsa);
827:       /* scan very first token */
828:       scan_token(dsa);

by the following one:

823:       dsa->lp = lpx_create_prob();
824:       lpx_create_index(dsa->lp);
     #if 0
825:       /* read very first character */
826:       read_char(dsa);
     #endif
827:       /* scan very first token */
828:       scan_token(dsa);

Another way to avoid the bug is to add an empty line to the beginning of
a text file in cplex lp format.


Andrew Makhorin