diff options
| -rw-r--r-- | libbuild2/cc/compile-rule.cxx | 6 | ||||
| -rw-r--r-- | libbuild2/cc/module.hxx | 27 |
2 files changed, 29 insertions, 4 deletions
diff --git a/libbuild2/cc/compile-rule.cxx b/libbuild2/cc/compile-rule.cxx index cebd244..99c3b90 100644 --- a/libbuild2/cc/compile-rule.cxx +++ b/libbuild2/cc/compile-rule.cxx @@ -3148,7 +3148,7 @@ namespace build2 } hk.file = move (fp); - hk.hash = hash<path> () (hk.file); + hk.hash = hash<string> () (hk.file.string ()); slock l (hc.header_map_mutex); auto i (hc.header_map.find (hk)); @@ -3201,7 +3201,7 @@ namespace build2 // path has changed (header has been remapped). // if (!e || r.second) - hk.hash = hash<path> () (hk.file); + hk.hash = hash<string> () (hk.file.string ()); const file* f; { @@ -3214,6 +3214,8 @@ namespace build2 { //cache_cls.fetch_add (1, memory_order_relaxed); + // @@ TMP cleanup. + // #if 0 assert (r.first == f); #else diff --git a/libbuild2/cc/module.hxx b/libbuild2/cc/module.hxx index 4213516..2ef07d6 100644 --- a/libbuild2/cc/module.hxx +++ b/libbuild2/cc/module.hxx @@ -92,13 +92,36 @@ namespace build2 // struct header_key { - path file; + // We used to use path comparison/hash which are case-insensitive on + // Windows. While this sounds right on the surface, the catch is that + // our target names are always case-sensitive, even on Windows. So + // what can happen is that the same header spelled in different case + // ends up with distinct targets but trying to occupy the same cache + // entry. See GH issue #390 for details. + // + // The conceptually correct way to fix this would be to actualize the + // header name. But that would be prohibitively expensive, especially + // on Windows. Plus the header may be generated and thus not yet + // exist. + // + // On the other hand, we can already end up with different targets + // mapped to the same filesystem entry in other situations (h{} vs + // hxx{} is the canonical example). And we are ok with that provided + // they have noop recipes. So it feels like the simplest solution here + // is to go along by having case-sensitive cache entries. This means + // that auto-generated headers will have to be included using the same + // spelling, but that seems like a sensible restriction (doing + // otherwise won't be portable). + // + path file; size_t hash; friend bool operator== (const header_key& x, const header_key& y) { - return x.file == y.file; // Note: hash was already compared. + // Note: hash was already compared. + // + return x.file.string () == y.file.string (); } }; |