To search for an erroneous pattern like this:
for (i = 0; i < n; i++) {}
...
if (i > n) ...This is wrong because at the end of the loop i equals n and cannot be greater than n. To match this:
gres -A40 "^ for \(" \
"for \( (@V) = @d ; \1 < @d ; \1 \+\+ \)
\{.8.\}
@n
if \( \1 > \3 \)" | lessThe first string is used to get the git grep query. To see what is queried for execute
bli2 "^ for \("It will print the extended regexp used in the query.
@V is translated to [[:alpha:]_]+[[:alnum:]_]*, which matches a local variable. @d matches any number in several formats, therefore it contains parentheses, that's why we use \3, as a back-reference to match the second @d. \{.8.\} matches anything between curly brackets, up to 8 nested curly brackets.
This results after about 10 seconds in a match:
---[ vi drivers/mmc/host/s3cmci.c +1209 ]---
/* Set clock */
for (mci_psc = 0; mci_psc < 255; mci_psc++) {
...
}
if (mci_psc > 255)
mci_psc = 255;
...Quite harmless so I left it.
I left this simple for explanatory reasons. A more advanced query to catch these errors, and others, can be found here [wiki:roelkluin/gres_tests/loops gres_tests/loops].
