diff options
Diffstat (limited to 'build2/algorithm.cxx')
| -rw-r--r-- | build2/algorithm.cxx | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/build2/algorithm.cxx b/build2/algorithm.cxx index 8ee6d47..6743907 100644 --- a/build2/algorithm.cxx +++ b/build2/algorithm.cxx @@ -1790,15 +1790,29 @@ namespace build2 // const target& g (*t.group); - if (execute (a, g) == target_state::busy) + target_state gs (execute (a, g)); + + if (gs == target_state::busy) sched.wait (target::count_executed (), g[a].task_count, scheduler::work_none); - // Indicate to execute() that this target's state comes from the group - // (which, BTW, can be failed). + // Return target_state::group to signal to execute() that this target's + // state comes from the group (which, BTW, can be failed). + // + // There is just one small problem: if the returned group state is + // postponed, then this means the group hasn't been executed yet. And if + // we return target_state::group, then this means any state queries (see + // executed_state()) will be directed to the target which might still not + // be executed or, worse, is being executed as we query. + // + // So in this case we return target_state::postponed (which will result in + // the member being treated as unchanged). This is how it is done for + // prerequisites and seeing that we've been acting as if the group is our + // prerequisite, there is no reason to deviate (see the recipe return + // value documentation for details). // - return target_state::group; + return gs != target_state::postponed ? target_state::group : gs; } target_state |