fix

addons/misra.py

@@ -422,6 +422,28 @@ def get_type_conversion_to_from(token):
 
     return None
 
+
+def is_composite_expr(expr, composite_operator=False):
+    """MISRA C 2012, section 8.10.3"""
+    if expr is None:
+        return False
+
+    if not composite_operator:
+        if (expr.str in ('+', '-', '*', '/', '%', '&', '|', '^', '>>', "<<", "?", ":", '~')):
+            return is_composite_expr(expr.astOperand1,True) or is_composite_expr(expr.astOperand2, True)
+        if expr.str == '?' and simpleMatch(expr.astOperand2, ':'):
+            colon = expr.astOperand2
+            return is_composite_expr(colon.astOperand1,True) or is_composite_expr(colon.astOperand2, True)
+        return False
+
+    # non constant expression?
+    if expr.isNumber:
+        return False
+    if expr.astOperand1 or expr.astOperand2:
+        return is_composite_expr(expr.astOperand1,True) or is_composite_expr(expr.astOperand2, True)
+    return True
+
+
 def getEssentialTypeCategory(expr):
     if not expr:
         return None
@@ -2277,8 +2299,7 @@ class MisraChecker:
         for token in data.tokenlist:
             if token.str != '=' or not token.astOperand1 or not token.astOperand2:
                 continue
-            if (token.astOperand2.str not in ('+', '-', '*', '/', '%', '&', '|', '^', '>>', "<<", "?", ":", '~') and
-                    not isCast(token.astOperand2)):
+            if not is_composite_expr(token.astOperand2):
                 continue
             vt1 = token.astOperand1.valueType
             vt2 = token.astOperand2.valueType

addons/test/misra/misra-test.c

@@ -623,7 +623,7 @@ static void misra_10_1(uint32_t u, char c1, char c2, uint8_t u8) {
   int32_t i;
   char c;
   enum { E1 = 1 };
-  i = 3 << 1; // 10.1 10.6
+  i = 3 << 1; // 10.1
   i = (u & u) << 4; // no-warning
   c = c1 & c2; // 10.1
   c = c1 << 1; // 10.1
@@ -736,10 +736,10 @@ static void misra_10_5(uint16_t x) {
 struct misra_10_6_s {
     unsigned int a:4;
 };
-static void misra_10_6(u8 x, u32 a, u32 b, char c1, char c2) {
-  u16 y = x+x; // 10.6
+static void misra_10_6(u8 x, char c1, char c2) {
+  u16 y1 = x+x; // 10.6
+  u16 y2 = (0x100u - 0x80u); // rhs is not a composite expression because it's a constant expression
   u16 z = ~u8 x ;//10.6
-  u32 c = ( u16) ( u32 a + u32 b ); //10.6
   s32 i = c1 - c2; // 10.3 FIXME: False positive for 10.6 (this is compliant). Trac #9488
   struct misra_10_6_s s;
   s.a = x & 1U; // no-warning (#10487)