* Sync with the trunk.

src/bsdiff-4.3/Makefile.am

@@ -1,3 +1,5 @@
+EXTRA_DIST = compat-include
+
 libexec_PROGRAMS = bsdiff bspatch
 
 bsdiff_SOURCES = bsdiff.c
@@ -8,4 +10,4 @@ bspatch_SOURCES = bspatch.c
 
 bspatch_LDADD = ${bzip2_lib}
 
-AM_CFLAGS = -O3 ${bzip2_include}
+AM_CFLAGS = -O3 ${bzip2_include} ${bsddiff_compat_include}

src/bsdiff-4.3/compat-include/err.h

@@ -0,0 +1,12 @@
+/* Simulate BSD's <err.h> functionality. */
+
+#ifndef COMPAT_ERR_H_INCLUDED
+#define COMPAT_ERR_H_INCLUDED 1
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#define err(rc,...)  do { fprintf(stderr,__VA_ARGS__); exit(rc); } while(0)
+#define errx(rc,...) do { fprintf(stderr,__VA_ARGS__); exit(rc); } while(0)
+
+#endif

src/libexpr/eval.cc

@@ -750,13 +750,15 @@ void ExprOpImpl::eval(EvalState & state, Env & env, Value & v)
 
 void ExprOpUpdate::eval(EvalState & state, Env & env, Value & v)
 {
-    Value v2;
-    state.evalAttrs(env, e1, v2);
-        
-    state.cloneAttrs(v2, v);
-        
+    Value v1, v2;
+    state.evalAttrs(env, e1, v1);
     state.evalAttrs(env, e2, v2);
-    
+
+    if (v1.attrs->size() == 0) { v = v2; return; }
+    if (v2.attrs->size() == 0) { v = v1; return; }
+
+    state.cloneAttrs(v1, v);
+
     foreach (Bindings::iterator, i, *v2.attrs) {
         Attr & a = (*v.attrs)[i->first];
         mkCopy(a.value, i->second.value);

src/libexpr/primops.cc

@@ -788,13 +788,13 @@ static void prim_intersectAttrs(EvalState & state, Value * * args, Value & v)
     state.forceAttrs(*args[1]);
         
     state.mkAttrs(v);
-    
-    foreach (Bindings::iterator, i, *args[1]->attrs) {
-        Bindings::iterator j = args[0]->attrs->find(i->first);
-        if (j != args[0]->attrs->end()) {
-            Attr & a = (*v.attrs)[i->first];
-            mkCopy(a.value, i->second.value);
-            a.pos = i->second.pos;
+
+    foreach (Bindings::iterator, i, *args[0]->attrs) {
+        Bindings::iterator j = args[1]->attrs->find(i->first);
+        if (j != args[1]->attrs->end()) {
+            Attr & a = (*v.attrs)[j->first];
+            mkCopy(a.value, j->second.value);
+            a.pos = j->second.pos;
         }
     }
 }

src/libmain/shared.cc

@@ -135,6 +135,7 @@ static void initAndRun(int argc, char * * argv)
     /* Get some settings from the configuration file. */
     thisSystem = querySetting("system", SYSTEM);
     maxBuildJobs = queryIntSetting("build-max-jobs", 1);
+    buildCores = queryIntSetting("build-cores", 1);
     maxSilentTime = queryIntSetting("build-max-silent-time", 0);
 
     /* Catch SIGINT. */
@@ -226,6 +227,8 @@ static void initAndRun(int argc, char * * argv)
             tryFallback = true;
         else if (arg == "--max-jobs" || arg == "-j")
             maxBuildJobs = getIntArg<unsigned int>(arg, i, args.end());
+        else if (arg == "--cores")
+            buildCores = getIntArg<unsigned int>(arg, i, args.end());
         else if (arg == "--readonly-mode")
             readOnlyMode = true;
         else if (arg == "--max-silent-time")

src/libstore/build.cc

@@ -25,6 +25,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include <stdio.h>
+#include <cstring>
 
 #include <pwd.h>
 #include <grp.h>
@@ -1427,6 +1428,9 @@ void DerivationGoal::startBuilder()
        in the store or in the build directory). */
     env["NIX_STORE"] = nixStore;
 
+    /* The maximum number of cores to utilize for parallel building. */
+    env["NIX_BUILD_CORES"] = (format("%d") % buildCores).str();
+
     /* Add all bindings specified in the derivation. */
     foreach (StringPairs::iterator, i, drv.env)
         env[i->first] = i->second;
@@ -2654,6 +2658,7 @@ void Worker::waitForInput()
         timeout.tv_sec = std::max((time_t) 0, lastWokenUp + wakeUpInterval - before);
     } else lastWokenUp = 0;
 
+    using namespace std;
     /* Use select() to wait for the input side of any logger pipe to
        become `available'.  Note that `available' (i.e., non-blocking)
        includes EOF. */

src/libstore/globals.cc

@@ -22,6 +22,7 @@ bool keepGoing = false;
 bool tryFallback = false;
 Verbosity buildVerbosity = lvlInfo;
 unsigned int maxBuildJobs = 1;
+unsigned int buildCores = 1;
 bool readOnlyMode = false;
 string thisSystem = "unset";
 time_t maxSilentTime = 0;

src/libstore/globals.hh

@@ -55,6 +55,11 @@ extern Verbosity buildVerbosity;
 /* Maximum number of parallel build jobs.  0 means unlimited. */
 extern unsigned int maxBuildJobs;
 
+/* Number of CPU cores to utilize in parallel within a build, i.e. by passing
+   this number to Make via '-j'. 0 means that the number of actual CPU cores on
+   the local host ought to be auto-detected. */
+extern unsigned int buildCores;
+
 /* Read-only mode.  Don't copy stuff to the store, don't change the
    database. */
 extern bool readOnlyMode;

src/libstore/remote-store.cc

@@ -13,6 +13,7 @@
 
 #include <iostream>
 #include <unistd.h>
+#include <cstring>
 
 
 namespace nix {
@@ -158,6 +159,7 @@ void RemoteStore::connectToDaemon()
     addr.sun_family = AF_UNIX;
     if (socketPathRel.size() >= sizeof(addr.sun_path))
         throw Error(format("socket path `%1%' is too long") % socketPathRel);
+    using namespace std;
     strcpy(addr.sun_path, socketPathRel.c_str());
     
     if (connect(fdSocket, (struct sockaddr *) &addr, sizeof(addr)) == -1)

src/libutil/util.cc

@@ -12,6 +12,7 @@
 #include <sys/types.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <limits.h>
 
 #include "util.hh"
 

src/nix-env/nix-env.cc

@@ -247,11 +247,12 @@ static DrvInfos filterBySelector(EvalState & state, const DrvInfos & allElems,
         }
 
         /* If `newestOnly', if a selector matches multiple derivations
-           with the same name, pick the one with the highest priority.
-           If there are multiple derivations with the same priority,
-           pick the one with the highest version.  If there are
-           multiple derivations with the same priority and name and
-           version, then pick the first one. */
+           with the same name, pick the one matching the current
+           system.  If there are still multiple derivations, pick the
+           one with the highest priority.  If there are still multiple
+           derivations, pick the one with the highest version.
+           Finally, if there are still multiple derivations,
+           arbitrarily pick the first one. */
         if (newestOnly) {
 
             /* Map from package names to derivations. */
@@ -266,7 +267,12 @@ static DrvInfos filterBySelector(EvalState & state, const DrvInfos & allElems,
                 Newest::iterator k = newest.find(drvName.name);
                 
                 if (k != newest.end()) {
-                    d = comparePriorities(state, j->first, k->second.first);
+                    d = j->first.system == k->second.first.system ? 0 :
+                        j->first.system == thisSystem ? 1 :
+                        k->second.first.system == thisSystem ? -1 : 0;
+                    printMsg(lvlError, format("%1% %2% %3% %4%") % j->first.system % k->second.first.system % thisSystem % d);
+                    if (d == 0)
+                        d = comparePriorities(state, j->first, k->second.first);
                     if (d == 0)
                         d = compareVersions(drvName.version, DrvName(k->second.first.name).version);
                 }
@@ -1230,7 +1236,7 @@ void run(Strings args)
     
     globals.instSource.type = srcUnknown;
     globals.instSource.nixExprPath = getDefNixExprPath();
-    globals.instSource.systemFilter = thisSystem;
+    globals.instSource.systemFilter = "*";
     
     globals.dryRun = false;
     globals.preserveInstalled = false;

src/nix-worker/nix-worker.cc

@@ -7,6 +7,7 @@
 #include "globals.hh"
 
 #include <iostream>
+#include <cstring>
 #include <unistd.h>
 #include <signal.h>
 #include <sys/types.h>
@@ -111,6 +112,7 @@ static bool isFarSideClosed(int socket)
    time and wouldn't have to worry about races. */
 static void sigPollHandler(int sigNo)
 {
+    using namespace std;
     try {
         /* Check that the far side actually closed.  We're still
            getting spurious signals every once in a while.  I.e.,