Restore depfile toleration of multiple output paths on distinct lines

Prior to introduction of depfile parser handling of multiple rules,
ninja silently accepted a depfile of the form:

    out: in1 in2 in3
    other: otherIn1 otherIn2 otherIn3

and incorrectly treated `other` and `otherIn*` as additional inputs to
`out`.  Now we prefer to reject this just as we already do for a depfile
specifying multiple outputs on one line.  However, this can break
existing cases where such a depfile was silently tolerated.

Add a `-w depfilemulti={err,warn}` option to control this behavior,
and make it just a warning by default.

1 files changed, 9 insertions, 4 deletions

diff --git a/src/graph.h b/src/graph.h
index a8f0641..d58fecd 100644
--- a/src/graph.h
+++ b/src/graph.h
@@ -24,6 +24,7 @@ using namespace std;
 #include "util.h"
 
 struct BuildLog;
+struct DepfileParserOptions;
 struct DiskInterface;
 struct DepsLog;
 struct Edge;
@@ -209,8 +210,10 @@ struct Edge {
 /// "depfile" attribute in build files.
 struct ImplicitDepLoader {
   ImplicitDepLoader(State* state, DepsLog* deps_log,
-                    DiskInterface* disk_interface)
-      : state_(state), disk_interface_(disk_interface), deps_log_(deps_log) {}
+                    DiskInterface* disk_interface,
+                    DepfileParserOptions const* depfile_parser_options)
+      : state_(state), disk_interface_(disk_interface), deps_log_(deps_log),
+        depfile_parser_options_(depfile_parser_options) {}
 
   /// Load implicit dependencies for \a edge.
   /// @return false on error (without filling \a err if info is just missing
@@ -242,6 +245,7 @@ struct ImplicitDepLoader {
   State* state_;
   DiskInterface* disk_interface_;
   DepsLog* deps_log_;
+  DepfileParserOptions const* depfile_parser_options_;
 };
 
 
@@ -249,10 +253,11 @@ struct ImplicitDepLoader {
 /// and updating the dirty/outputs_ready state of all the nodes and edges.
 struct DependencyScan {
   DependencyScan(State* state, BuildLog* build_log, DepsLog* deps_log,
-                 DiskInterface* disk_interface)
+                 DiskInterface* disk_interface,
+                 DepfileParserOptions const* depfile_parser_options)
       : build_log_(build_log),
         disk_interface_(disk_interface),
-        dep_loader_(state, deps_log, disk_interface) {}
+        dep_loader_(state, deps_log, disk_interface, depfile_parser_options) {}
 
   /// Update the |dirty_| state of the given node by inspecting its input edge.
   /// Examine inputs, outputs, and command lines to judge whether an edge