1 files changed, 15 insertions, 6 deletions

diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index 11195af77..f94c23ea7 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -43,13 +43,14 @@ static char * dupString(const char * s)
 }
 
 
+/* Note: Various places expect the allocated memory to be zeroed. */
 static void * allocBytes(size_t n)
 {
     void * p;
 #if HAVE_BOEHMGC
     p = GC_malloc(n);
 #else
-    p = malloc(n);
+    p = calloc(n, 1);
 #endif
     if (!p) throw std::bad_alloc();
     return p;
@@ -293,6 +294,10 @@ EvalState::EvalState(const Strings & _searchPath, ref<Store> store)
     , sWrong(symbols.create("wrong"))
     , sStructuredAttrs(symbols.create("__structuredAttrs"))
     , sBuilder(symbols.create("builder"))
+    , sArgs(symbols.create("args"))
+    , sOutputHash(symbols.create("outputHash"))
+    , sOutputHashAlgo(symbols.create("outputHashAlgo"))
+    , sOutputHashMode(symbols.create("outputHashMode"))
     , repair(NoRepair)
     , store(store)
     , baseEnv(allocEnv(128))
@@ -308,7 +313,7 @@ EvalState::EvalState(const Strings & _searchPath, ref<Store> store)
         for (auto & i : _searchPath) addToSearchPath(i);
         for (auto & i : paths) addToSearchPath(i);
     }
-    addToSearchPath("nix=" + settings.nixDataDir + "/nix/corepkgs");
+    addToSearchPath("nix=" + canonPath(settings.nixDataDir + "/nix/corepkgs", true));
 
     if (settings.restrictEval || settings.pureEval) {
         allowedPaths = PathSet();
@@ -404,7 +409,7 @@ Path EvalState::toRealPath(const Path & path, const PathSet & context)
 };
 
 
-void EvalState::addConstant(const string & name, Value & v)
+Value * EvalState::addConstant(const string & name, Value & v)
 {
     Value * v2 = allocValue();
     *v2 = v;
@@ -412,12 +417,18 @@ void EvalState::addConstant(const string & name, Value & v)
     baseEnv.values[baseEnvDispl++] = v2;
     string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name;
     baseEnv.values[0]->attrs->push_back(Attr(symbols.create(name2), v2));
+    return v2;
 }
 
 
 Value * EvalState::addPrimOp(const string & name,
     unsigned int arity, PrimOpFun primOp)
 {
+    if (arity == 0) {
+        Value v;
+        primOp(*this, noPos, nullptr, v);
+        return addConstant(name, v);
+    }
     Value * v = allocValue();
     string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name;
     Symbol sym = symbols.create(name2);
@@ -576,9 +587,7 @@ Env & EvalState::allocEnv(unsigned int size)
     Env * env = (Env *) allocBytes(sizeof(Env) + size * sizeof(Value *));
     env->size = size;
 
-    /* Clear the values because maybeThunk() and lookupVar fromWith expect this. */
-    for (unsigned i = 0; i < size; ++i)
-        env->values[i] = 0;
+    /* We assume that env->values has been cleared by the allocator; maybeThunk() and lookupVar fromWith expect this. */
 
     return *env;
 }