introduce ability to build projects for the host system

when qmake runs into the new option(host_build) command, it will restart
the project evaluation with a host spec.

the new default host spec is called default-host (gasp!). it is
overridden with the pre-exising -spec / -platform option, while the new
-xspec / -xplatform option overrides the pre-existing default spec.
specifying -spec but not -xspec will set the xspec, too, so the behavior
is backwards-compatible. same for the XQMAKESPEC override read from
.qmake.cache and the environment variable.
the cleaner solution would be adding -hostspec, to be symmetrical with
the override semantics, but that would deviate from configure in turn.

Change-Id: I4297c873780af16ab7928421b434ce0f1d3820da
Reviewed-by: Joerg Bornemann <joerg.bornemann@nokia.com>

1 files changed, 14 insertions, 1 deletions

diff --git a/qmake/option.cpp b/qmake/option.cpp
index de907f0528..836cc3f492 100644
--- a/qmake/option.cpp
+++ b/qmake/option.cpp
@@ -107,6 +107,7 @@ QStringList Option::projfile::project_dirs;
 
 //QMAKE_GENERATE_MAKEFILE stuff
 QString Option::mkfile::qmakespec;
+QString Option::mkfile::xqmakespec;
 int Option::mkfile::cachefile_depth = -1;
 bool Option::mkfile::do_deps = true;
 bool Option::mkfile::do_mocs = true;
@@ -117,6 +118,7 @@ bool Option::mkfile::do_cache = true;
 QString Option::mkfile::cachefile;
 QStringList Option::mkfile::project_files;
 QString Option::mkfile::qmakespec_commandline;
+QString Option::mkfile::xqmakespec_commandline;
 
 static Option::QMAKE_MODE default_mode(QString progname)
 {
@@ -327,6 +329,9 @@ Option::parseCommandLine(int argc, char **argv, int skip)
                     } else if(opt == "platform" || opt == "spec") {
                         Option::mkfile::qmakespec = cleanSpec(argv[++x]);
                         Option::mkfile::qmakespec_commandline = argv[x];
+                    } else if (opt == "xplatform" || opt == "xspec") {
+                        Option::mkfile::xqmakespec = cleanSpec(argv[++x]);
+                        Option::mkfile::xqmakespec_commandline = argv[x];
                     } else {
                         fprintf(stderr, "***Unknown option -%s\n", opt.toLatin1().constData());
                         return Option::QMAKE_CMDLINE_SHOW_USAGE | Option::QMAKE_CMDLINE_ERROR;
@@ -381,6 +386,9 @@ Option::parseCommandLine(int argc, char **argv, int skip)
     if (!user_configs.isEmpty())
         Option::before_user_vars += "CONFIG += " + user_configs.join(" ");
 
+    if (Option::mkfile::xqmakespec.isEmpty())
+        Option::mkfile::xqmakespec = Option::mkfile::qmakespec;
+
     return Option::QMAKE_CMDLINE_SUCCESS;
 }
 
@@ -536,8 +544,13 @@ Option::init(int argc, char **argv)
     //last chance for defaults
     if(Option::qmake_mode == Option::QMAKE_GENERATE_MAKEFILE ||
         Option::qmake_mode == Option::QMAKE_GENERATE_PRL) {
-        if(Option::mkfile::qmakespec.isNull() || Option::mkfile::qmakespec.isEmpty())
+        if (Option::mkfile::xqmakespec.isEmpty())
+            Option::mkfile::xqmakespec = QString::fromLocal8Bit(qgetenv("XQMAKESPEC").constData());
+        if (Option::mkfile::qmakespec.isEmpty()) {
             Option::mkfile::qmakespec = QString::fromLocal8Bit(qgetenv("QMAKESPEC").constData());
+            if (Option::mkfile::xqmakespec.isEmpty())
+                Option::mkfile::xqmakespec = Option::mkfile::qmakespec;
+        }
 
         //try REALLY hard to do it for them, lazy..
         if(Option::mkfile::project_files.isEmpty()) {