rules: Propagate PATH list from defaults

... instead of creating an ENV from it and propagating this.
The idea is to keep PATH entries separate and only join them
with ":" when we need it. In this way, we can accumulate
PATHs from multiple defaults later, and perform a
deduplication ("nub_left") to shorten the final string
length.

1 files changed, 31 insertions, 0 deletions

diff --git a/CC/EXPRESSIONS b/CC/EXPRESSIONS
index 2a5011d..b718f76 100644
--- a/CC/EXPRESSIONS
+++ b/CC/EXPRESSIONS
@@ -1223,6 +1223,7 @@
     , "flags": "flags"
     , "objects": "objects"
     , "default-ENV": "default-ENV"
+    , "default-PATH": "default-PATH"
     , "default-LDFLAGS": "default-LDFLAGS"
     , "default-TOOLCHAIN": "default-TOOLCHAIN"
     , "default-NON_SYSTEM_TOOLS": "default-NON_SYSTEM_TOOLS"
@@ -1271,6 +1272,36 @@
             ]
           }
         ]
+      , [ "ENV_PATH"
+        , { "type": "lookup"
+          , "map": {"type": "var", "name": "ENV"}
+          , "key": "PATH"
+          }
+        ]
+      , [ "ENV"
+        , { "type": "map_union"
+          , "$1":
+            [ {"type": "var", "name": "ENV"}
+            , { "type": "singleton_map"
+              , "key": "PATH"
+              , "value":
+                { "type": "join"
+                , "separator": ":"
+                , "$1":
+                  { "type": "++"
+                  , "$1":
+                    [ {"type": "CALL_EXPRESSION", "name": "default-PATH"}
+                    , { "type": "if"
+                      , "cond": {"type": "var", "name": "ENV_PATH"}
+                      , "then": [{"type": "var", "name": "ENV_PATH"}]
+                      }
+                    ]
+                  }
+                }
+              }
+            ]
+          }
+        ]
       , ["objects", {"type": "CALL_EXPRESSION", "name": "objects"}]
       , [ "base name"
         , { "type": "if"