There are still some known bugs in INTERCAL (and no doubt many we don’t even suspect as yet). The following list accumulates current bug reports and TO DO agenda items through the current release.

ESR = Eric S. Raymond SS = Steve Swales LHH = Louis Howell BLR = Brian Raiter AIS = Alex Smith

Known Bugs

  1. (ESR) INTERCAL would be intrinsically a crock even if it worked right.

  2. (BLR) I have hacked up a fix to the problem with line numbers being off due to statements sharing/spanning lines. The parser now stores the starting line number for all tuples, not just the splatted ones. Not only does this give synchronized lines in the comments in the degenerated C code, but run-time error messages are just as reliable as the parse/compile-time ones. The line number in the error message is actually the line number of the next statement (e.g., if the next statement is on the same line, the line number of both statements will be used). 

    Note that I said "just as reliable," as opposed to "fully
reliable". Since the lexer doesn't know where the line ends until
after it's already parsed the preamble (DO-PLEASE combo, line
label, oh-oh-seven number, etc) of the following line, it actually
stores as the starting line number the first non-whitespace of the
statement proper. So if a statement has its preamble on one line
and the rest of it on the next, the preamble will be beheaded.
    Still, it's a vast improvement, and as LHH pointed out, it's not
going to get much better without writing a preprocessing lexer that
can actually separate out the statements before any real parsing
begins. Until someone wants to do that, this will do nicely, I think.
    As a side bonus, splatting now shows the entire statement. (Er,
except when the statement both spans and shares a line. If a multi-
line statement ends on the same line as the beginning of the next
statement, the last part will get truncated. Again, not a case we
want to be encouraging people to explore anyway.)

  3. (BLR) Interleave does not check the type of its arguments. The manual insinuates that interleaving 32-bit values should result in error 533; instead, C-INTERCAL silently truncates them to 16 bits. Unfortunately, the modified behavior of select’s return type depends on this, so there’s not much we can do about it as things stand.

  4. (AIS) Reverse assignments (those with the expression on the left) are very unlikely to work in bases other than 2. (The current code calculates what the answer would be in base 2 and throws an error if it isn’t correct for the current base.)

  5. (AIS) Some of the newer features in intercal.el are not yet fully implemented and have a tendency to print Unimplemented rather than doing anything useful.

  6. (AIS) The external call system only works with gcc (due to its need to pass command-line arguments like -x and -E to it), and fails when mixed with come-from-gerund and next-from-gerund.

To Do

  1. (ESR) Add more optimization templates, esp. idioms for +, -, *, /.

  2. (ESR) Forget this @!%$#! crock and take a long vacation.