diff options
Diffstat (limited to 'libbuild2/rule.hxx')
| -rw-r--r-- | libbuild2/rule.hxx | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/libbuild2/rule.hxx b/libbuild2/rule.hxx index da069ef..913c597 100644 --- a/libbuild2/rule.hxx +++ b/libbuild2/rule.hxx @@ -22,7 +22,8 @@ namespace build2 // you need to modify some state (e.g., counters or some such), then make // sure things are MT-safe. // - // Note: match() is only called once but may not be followed by apply(). + // Note: match() could be called multiple times (so should be idempotent) + // and it may not be followed by apply(). // // The hint argument is the rule hint, if any, that was used to select this // rule. While normally not factored into the match decision, a rule may @@ -72,10 +73,11 @@ namespace build2 // only if our update rule also matches. // // Arranging this, however, is not a simple matter of calling the other - // rule's match(): we also have to take into account the rule hints for - // that operation. This helper performs all the necessary steps. Note: - // should only be called from match() (see target::find_hint() for - // details). + // rule's match(): we also have to take into account ad hoc recipes and + // rule hints for that operation. This helper performs all the necessary + // checks. Note: should only be called from match() (see + // target::find_hint() for details). Note also that ad hoc recipes are + // checked for hint_op, not action's operation. // bool sub_match (const string& rule_name, operation_id hint_op, |