Getting a table out of a GLPK solution throws error "Assertion failed: out != out" - glpk

Question

I have a linear program in a file lp that GLPK solves with this command:
glpsol --math -m lp
Part of the output on the screen is:
Generating priority_words...
Model has been successfully generated
...
Long-step dual simplex will be used
+ 770: mip = not found yet <= +inf (1; 0)
Solution found by heuristic: 1569225
...
INTEGER OPTIMAL SOLUTION FOUND
...
Writing MIP solution to 'result'...
The file result is unformatted and I want to save the results in CSV. So I include a line to output the results to a table right after the last constraint and before the end; keyword:
...
s.t. priority_words{w in words}: include[w] >= priority[w];
table num{u in unicodes} OUT "CSV" "num.csv": u~unicode, number_of_characters[u]~count;
end;
And GLPK gives this error:
Generating priority_words...
Writing num...
Assertion failed: out != out
Error detected in file mpl/mpl3.c at line 5072
Abort trap: 6
Neither the wikibook nor the gmpl manual in the distribution (at doc/gmpl.pdf) have an example of getting a table out of GLPK.
How can I ask GLPK for a table of results after solving the model?

Answer 1

Note that the output for the code with the table OUT statement does not have the line Model has been successfully generated. Therefore GLPK attempted to write the table of results before solving the problem! The sample code in this thread shows that GLPK needs to know when to solve the problem, otherwise it solves it at the end. So just add solve; before the table:
...
s.t. priority_words{w in words}: include[w] >= priority[w];
solve;
table num{u in unicodes} OUT "CSV" "num.csv": u~unicode, number_of_characters[u]~count;
end;

Answer 2

Neither the wikibook nor the gmpl manual in the distribution (at doc/gmpl.pdf) have an example of getting a table out of GLPK.
The current version of GLPK is 4.65. The lines below relate to this version.
Examples are in:
examples/csv
examples/sql
examples/dbf
doc/gmpl.pdf has a chapter on the table statement.