Merge pull request ARMmbed#12303 from rajkan01/fix_micro_lib_warning

Fix ARM compiler warning for microlib

Author: adbridge

tools/test/toolchains/test_toolchains.py

@@ -64,9 +64,7 @@ def test_arm_c_lib(self):
 
         self.assertIn("--library_type=microlib", arm_std_obj.flags["ld"])
         self.assertIn("--library_type=microlib", arm_micro_obj.flags["ld"])
-        self.assertIn("--library_type=microlib", arm_c6_obj.flags["ld"])
-
-        self.assertIn("-Wl,--library_type=microlib", arm_c6_obj.flags["cxx"])
+        self.assertIn("--library_type=microlib", arm_c6_obj.flags["ld"])        
         self.assertIn("--library_type=microlib", arm_c6_obj.flags["asm"])
 
     def test_arm_c_lib_std_exception(self):

tools/toolchains/arm.py

@@ -581,10 +581,6 @@ def __init__(self, target, *args, **kwargs):
                 self.flags['common'].append("-D__MICROLIB")
             if "--library_type=microlib" not in self.flags['ld']:
                 self.flags['ld'].append("--library_type=microlib")
-            if "-Wl,--library_type=microlib" not in self.flags['c']:
-                self.flags['c'].append("-Wl,--library_type=microlib")
-            if "-Wl,--library_type=microlib" not in self.flags['cxx']:
-                self.flags['cxx'].append("-Wl,--library_type=microlib")
             if "--library_type=microlib" not in self.flags['asm']:
                 self.flags['asm'].append("--library_type=microlib")