fix configure error after host changed

xmake/actions/config/main.lua

@@ -34,6 +34,11 @@ function _option_filter(name)
     return name and name ~= "target" and name ~= "file" and name ~= "project" and name ~= "verbose"
 end
 
+-- host changed?
+function _host_changed(targetname)
+    return os.host() ~= config.read("host", targetname)
+end
+
 -- need check
 function _need_check()
 
@@ -194,7 +199,7 @@ function main()
     end
 
     -- merge the cached configure
-    if not option.get("clean") then
+    if not option.get("clean") and not _host_changed(targetname) then
         config.load(targetname)
     end
 

xmake/core/project/config.lua

@@ -39,6 +39,32 @@ function config._file()
     return path.join(config.directory(), "xmake.conf")
 end
 
+-- load the project configure
+function config._load(targetname)
+
+    -- check
+    targetname = targetname or "all"
+
+    -- load configure from the file first
+    local filepath = config._file()
+    if os.isfile(filepath) then
+
+        -- load it 
+        local results, errors = io.load(filepath)
+        if not results then
+            return nil, errors
+        end
+
+        -- load the target configure 
+        if results._TARGETS then
+            return table.wrap(results._TARGETS[targetname])
+        end
+    end
+
+    -- empty
+    return {}
+end
+
 -- get the current given configure
 function config.get(name)
 
@@ -98,29 +124,16 @@ end
 -- load the project configure
 function config.load(targetname)
 
-    -- check
-    targetname = targetname or "all"
-
-    -- load configure from the file first
-    local filepath = config._file()
-    if os.isfile(filepath) then
-
-        -- load it 
-        local results, errors = io.load(filepath)
+    local results, errors = config._load(targetname)
+    if not results then
+        utils.error(errors)
+        return true
+    end
 
-        -- error?
-        if not results then
-            utils.error(errors)
-            return true
-        end
-
-        -- merge the target configure first
-        if results._TARGETS then
-            for name, value in pairs(table.wrap(results._TARGETS[targetname])) do
-                if config.get(name) == nil then
-                    config.set(name, value)
-                end
-            end
+    -- merge the target configure first
+    for name, value in pairs(results) do
+        if config.get(name) == nil then
+            config.set(name, value)
         end
     end
 
@@ -161,6 +174,25 @@ function config.save(targetname)
     return io.save(config._file(), results) 
 end
 
+-- read value from the configure file directly
+function config.read(name, targetname)
+
+    -- load configs
+    local configs = config._load(targetname)
+
+    -- get it
+    local value = nil
+    if configs then
+        value = configs[name]
+        if type(value) == "string" and value == "auto" then
+            value = nil
+        end
+    end
+
+    -- ok?
+    return value
+end
+
 -- init the config
 function config.init()
 

xmake/core/sandbox/modules/import/core/project/config.lua

@@ -109,6 +109,13 @@ function sandbox_core_project_config.save(targetname)
     end
 end
 
+-- read the value from the configure file directly
+function sandbox_core_project_config.read(name, targetname)
+
+    -- read it
+    return config.read(name, targetname)
+end
+
 -- the configure has been changed for the given target?
 function sandbox_core_project_config.changed(targetname)