no need to save slash_bits, add comment

1 files changed, 9 insertions, 9 deletions

diff --git a/src/deps_log.cc b/src/deps_log.cc
index 9514446..fc46497 100644
--- a/src/deps_log.cc
+++ b/src/deps_log.cc
@@ -30,7 +30,7 @@
 // The version is stored as 4 bytes after the signature and also serves as a
 // byte order mark. Signature and version combined are 16 bytes long.
 const char kFileSignature[] = "# ninjadeps\n";
-const int kCurrentVersion = 4;
+const int kCurrentVersion = 3;
 
 // Record size is currently limited to less than the full 32 bit, due to
 // internal buffers having to have this size.
@@ -233,16 +233,19 @@ bool DepsLog::Load(const string& path, State* state, string* err) {
       if (!UpdateDeps(out_id, deps))
         ++unique_dep_record_count;
     } else {
-      int path_size = size - 8;
+      int path_size = size - 4;
       assert(path_size > 0);  // CanonicalizePath() rejects empty paths.
       // There can be up to 3 bytes of padding.
       if (buf[path_size - 1] == '\0') --path_size;
       if (buf[path_size - 1] == '\0') --path_size;
       if (buf[path_size - 1] == '\0') --path_size;
       StringPiece path(buf, path_size);
-      unsigned int slash_bits =
-          *reinterpret_cast<unsigned int*>(buf + size - 8);
-      Node* node = state->GetNode(path, slash_bits);
+      // It is not necessary to pass in a correct slash_bits here. It will
+      // either be a Node that's in the manifest (in which case it will already
+      // have a correct slash_bits that GetNode will look up), or it is an
+      // implicit dependency from a .d which does not affect the build command
+      // (and so need not have its slashes maintained).
+      Node* node = state->GetNode(path, 0);
 
       // Check that the expected index matches the actual index. This can only
       // happen if two ninja processes write to the same deps log concurrently.
@@ -382,7 +385,7 @@ bool DepsLog::RecordId(Node* node) {
   int path_size = node->path().size();
   int padding = (4 - path_size % 4) % 4;  // Pad path to 4 byte boundary.
 
-  unsigned size = path_size + padding + 4 + 4;
+  unsigned size = path_size + padding + 4;
   if (size > kMaxRecordSize) {
     errno = ERANGE;
     return false;
@@ -395,9 +398,6 @@ bool DepsLog::RecordId(Node* node) {
   }
   if (padding && fwrite("\0\0", padding, 1, file_) < 1)
     return false;
-  unsigned int slash_bits = node->slash_bits();
-  if (fwrite(&slash_bits, 4, 1, file_) < 1)
-    return false;
   int id = nodes_.size();
   unsigned checksum = ~(unsigned)id;
   if (fwrite(&checksum, 4, 1, file_) < 1)