diff -r a375e31bf312 -r c1298e7ffe3a targets/XSD_toolchain_gcc
--- a/targets/XSD_toolchain_gcc	Sun Mar 05 00:38:25 2017 +0000
+++ b/targets/XSD_toolchain_gcc	Fri Mar 24 12:07:47 2017 +0000
@@ -1,5 +1,5 @@
 
           <xsd:attribute name="Compiler" type="xsd:string" use="optional" default="gcc"/>
-          <xsd:attribute name="CFLAGS" type="xsd:string" use="required"/>
+          <xsd:attribute name="CFLAGS" type="xsd:string" use="optional" default=""/>
           <xsd:attribute name="Linker" type="xsd:string" use="optional" default="gcc"/>
-          <xsd:attribute name="LDFLAGS" type="xsd:string" use="required"/>
+          <xsd:attribute name="LDFLAGS" type="xsd:string" use="optional" default=""/>