From 48190ccfca933ac07f7b480bd92da0d6e399b630 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Mon, 30 May 2005 12:16:22 +0000
Subject: [PATCH] * Handle the case where all the direct references of a path
 are in the   selection but some indirect reference isn't (in which case the
 path   should still be rewritten).

---
 src/libstore/build.cc |  2 --
 src/libstore/misc.cc  | 57 +++++++++++++++++++++++++------------------
 2 files changed, 33 insertions(+), 26 deletions(-)

diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index ce4b59901..bbd212c0a 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -995,8 +995,6 @@ bool DerivationGoal::prepareBuild()
     for (Replacements::iterator i = replacements.begin();
          i != replacements.end(); ++i)
     {
-        printMsg(lvlError, format("FOO %1% %2%")
-            % i->first % i->second);
         printMsg(lvlError, format("HASH REWRITE %1% %2%")
             % hashPartOf(i->first).toString() % hashPartOf(i->second).toString());
         rewrites2[hashPartOf(i->first)] = hashPartOf(i->second);
diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc
index 009e0fd7d..80b2ba792 100644
--- a/src/libstore/misc.cc
+++ b/src/libstore/misc.cc
@@ -105,8 +105,11 @@ static void findBestRewrite(const ClassMap::const_iterator & pos,
 
 static Path maybeRewrite(const Path & path, const PathSet & selection,
     const FinalClassMap & finalClassMap,
-    Replacements & replacements)
+    Replacements & replacements,
+    unsigned int & nrRewrites)
 {
+    startNest(nest, lvlError, format("considering rewriting `%1%'") % path);
+
     assert(selection.find(path) != selection.end());
 
     if (replacements.find(path) != replacements.end()) return replacements[path];
@@ -115,34 +118,35 @@ static Path maybeRewrite(const Path & path, const PathSet & selection,
     queryReferences(noTxn, path, references);
 
     HashRewrites rewrites;
+    PathSet newReferences;
     
-    bool okay = true;
     for (PathSet::iterator i = references.begin(); i != references.end(); ++i) {
-        if (*i == path) continue; /* ignore self-references */
-        if (selection.find(*i) == selection.end()) {
-            OutputEqClasses classes;
-            queryOutputEqClasses(noTxn, *i, classes);
-            
-            if (classes.size() > 0) /* !!! hacky; ignore sources; they
-                                       are not in any eq class */
-            {
-                printMsg(lvlError, format("in `%1%': missing `%2%'") % path % *i);
-                okay = false;
 
-                FinalClassMap::const_iterator j = finalClassMap.find(*(classes.begin()));
-                assert(j != finalClassMap.end());
+        OutputEqClasses classes;
+        queryOutputEqClasses(noTxn, *i, classes);
 
-                printMsg(lvlError, format("replacing with `%1%'") % j->second);
-                
-                Path newPath = maybeRewrite(j->second, selection,
-                    finalClassMap, replacements);
-                if (*i != newPath)
-                    rewrites[hashPartOf(*i)] = hashPartOf(newPath);
-            }
+        /* !!! hacky; ignore sources; they are not in any eq class */
+        if (*i == path || classes.size() == 0) {
+            newReferences.insert(*i);
+            continue; /* ignore self-references */
         }
+
+        FinalClassMap::const_iterator j = finalClassMap.find(*(classes.begin()));
+        assert(j != finalClassMap.end());
+        
+        Path newPath = maybeRewrite(j->second, selection,
+            finalClassMap, replacements, nrRewrites);
+
+        if (*i != newPath)
+            rewrites[hashPartOf(*i)] = hashPartOf(newPath);
+
+        references.insert(newPath);
     }
 
-    if (rewrites.size() == 0) return path;
+    if (rewrites.size() == 0) {
+        replacements[path] = path;
+        return path;
+    }
 
     printMsg(lvlError, format("rewriting `%1%'") % path);
 
@@ -150,6 +154,8 @@ static Path maybeRewrite(const Path & path, const PathSet & selection,
         hashPartOf(path), namePartOf(path),
         references, rewrites);
 
+    nrRewrites++;
+
     printMsg(lvlError, format("rewrote `%1%' to `%2%'") % path % newPath);
 
     replacements[path] = newPath;
@@ -206,10 +212,13 @@ PathSet consolidatePaths(const PathSet & paths, bool checkOnly,
                 finalClassMap[i->first] = *j;
 
     PathSet newPaths;
+    unsigned int nrRewrites = 0;
     replacements.clear();
     for (PathSet::iterator i = bestSelection.begin();
          i != bestSelection.end(); ++i)
-        newPaths.insert(maybeRewrite(*i, bestSelection, finalClassMap, replacements));
-    
+        newPaths.insert(maybeRewrite(*i, bestSelection, finalClassMap, replacements, nrRewrites));
+
+    assert(nrRewrites == bestCost);
+
     return newPaths;
 }