diff options
| -rw-r--r-- | build2/context.cxx | 36 | ||||
| -rw-r--r-- | build2/scope.cxx | 15 | ||||
| -rw-r--r-- | build2/variable.hxx | 14 |
3 files changed, 48 insertions, 17 deletions
diff --git a/build2/context.cxx b/build2/context.cxx index 7b473e20..633f3ff6 100644 --- a/build2/context.cxx +++ b/build2/context.cxx @@ -682,27 +682,45 @@ namespace build2 c == '%' ? variable_visibility::project : variable_visibility::normal); - const variable& var (vp.insert (n, true)); // Allow overrides. + variable& var (const_cast<variable&> ( + vp.insert (n, true /* overridable */))); const char* k (tt == token_type::assign ? ".__override" : tt == token_type::append ? ".__suffix" : ".__prefix"); // We might already have a variable for this kind of override. // - const variable* o (&var); // Step behind. - for (; o->override != nullptr; o = o->override.get ()) + const variable* o (var.override.get ()); + for (; o != nullptr; o = o->override.get ()) { - if (o->override->visibility == v && - o->override->name.rfind (k) != string::npos) + if (o->visibility == v && o->name.rfind (k) != string::npos) break; } // Add it if not found. // - if (o->override == nullptr) - const_cast<variable*> (o)->override.reset ( - new variable {n + k, nullptr , nullptr, nullptr, v}); + if (o == nullptr) + { + unique_ptr<variable> p ( + new variable { + n + k, + nullptr /* alias */, + nullptr /* type */, + nullptr /* override */, + v}); + + // Back link. + // + p->alias = p.get (); + if (var.override != nullptr) + swap (p->alias, const_cast<variable*> (var.override.get ())->alias); - o = o->override.get (); + // Forward link. + // + p->override = move (var.override); + var.override = move (p); + + o = var.override.get (); + } // Currently we expand project overrides in the global scope to keep // things simple. Pass original variable for diagnostics. Use current diff --git a/build2/scope.cxx b/build2/scope.cxx index 69ab4b64..4dd475dc 100644 --- a/build2/scope.cxx +++ b/build2/scope.cxx @@ -397,6 +397,9 @@ namespace build2 // Then look for an __override that applies. // + // Note that the override list is in the reverse order of appearance and + // so we will naturally see the most recent override first. + // for (const variable* o (var.override.get ()); o != nullptr; o = o->override.get ()) @@ -488,14 +491,18 @@ namespace build2 { ++ovr_depth; - // Skip any append/prepend overrides that appear before __override, - // provided it is from this scope. + // The override list is in the reverse order of appearance so we need to + // iterate backwards in order to apply things in the correct order. + // + // We also need to skip any append/prepend overrides that appear before + // __override (in the command line order), provided it is from this + // scope. // bool skip (stem_ovr != nullptr && stem_depth == ovr_depth); - for (const variable* o (var.override.get ()); + for (const variable* o (var.override->alias); // Last override. o != nullptr; - o = o->override.get ()) + o = (o->alias != var.override->alias ? o->alias : nullptr)) { if (skip) { diff --git a/build2/variable.hxx b/build2/variable.hxx index 51e6eedc..2bdfe30d 100644 --- a/build2/variable.hxx +++ b/build2/variable.hxx @@ -149,10 +149,16 @@ namespace build2 // variable itself). // // If the variable is overridden on the command line, then override is the - // chain of the special override variables. Their names are derived from the - // main variable name as <name>.{__override,__prefix,__suffix} and they are - // not entered into the var_pool. The override variables only vary in their - // names and visibility. Their alias pointer is always NULL. + // linked list of the special override variables. Their names are derived + // from the main variable name as <name>.{__override,__prefix,__suffix} and + // they are not entered into the var_pool. The override variables only vary + // in their names and visibility. Their alias pointer is re-purposed to make + // the list doubly-linked with the first override's alias pointing to the + // last element (or itself). + // + // Note that the override list is in the reverse order of the overrides + // appearing on the command line, which is important when deciding whether + // and in what order they apply (see find_override() for details). // // Note also that we don't propagate the variable type to override variables // and we keep override values as untyped names. They get "typed" when they |