Unable to use an arbitrary expression for an index value under Systemtap
Issue
- The following Systemtap script returns a parse error, when an arbitrary expressions is used for an index value:
# cat ./example.stp
#!/usr/bin/stapprobe module("ext4").function("ext4_set_acl") {
if ($inode->i_ino == $1) {
for (i = 0; i < $acl->a_count; i++) {
if (($acl->a_entries[$i]->e_tag) & 0x2) {
printf ("\tacl: %s\n", $acl->a_entries[$i]$$)
}
}
}
}
# ./example.stp 157922
parse error: expected number
saw: identifier '$i' at ./example.stp:5:38
source: if (($acl->a_entries[$i]->e_tag) & 0x2) {
^
1 parse error(s).
Pass 1: parse failed. Try again with another '--vp 1' option.
#
Environment
- Red Hat Enterprise Linux 5.4
- Systemtap 0.9.7
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