misra: fix rule 5.4 false positive when macro is defined 'twice' inside #if/#else (#2125)

Author: conradoplg

addons/misra.py

@@ -880,7 +880,8 @@ def misra_5_4(self, data):
 
         for x, m_var1 in enumerate(macro):
             for y, m_var2 in enumerate(macro):
-                if x < y and macro[m_var1]["name"][:num_sign_chars] == macro[m_var2]["name"][:num_sign_chars]:
+                if x < y and macro[m_var1]["name"] != macro[m_var2]["name"] and \
+                    macro[m_var1]["name"][:num_sign_chars] == macro[m_var2]["name"][:num_sign_chars]:
                     if m_var1.linenr > m_var2.linenr:
                         self.reportError(m_var1, 5, 4)
                     else:

addons/test/misra/misra-test.c

@@ -104,6 +104,11 @@ void misra_5_3_enum_hidesfunction_31y(void) {} //5.3
 #define misra_5_4_macro_hides_macro__31y 2 //5.4
 #define m1(misra_5_4_param_hides_macro__31y) 1 //5.4
 #define m2(misra_5_4_param_hides_param__31x,misra_5_4_param_hides_param__31y) 1 //5.4
+#ifdef misra_5_4_macro_hides_macro__31x
+#define misra_5_4_macro 1 // no warning
+#else
+#define misra_5_4_macro 2 // no warning
+#endif
 
 #define misra_5_5_var_hides_macro____31x 1
 #define misra_5_5_functionhides_macro31x 1