C++: Added query that detects implicit function declarations

cpp/ql/test/query-tests/Likely Bugs/Underspecified Functions/ImplicitFunctionDeclaration.expected

@@ -0,0 +1,9 @@
+| test.c:28:3:28:12 | call to undeclared | Function call implicitly declares $@ | test.c:28:3:28:12 | call to undeclared | call to undeclared |
+| test.c:31:3:31:19 | call to not_yet_declared1 | Function call implicitly declares $@ | test.c:31:3:31:19 | call to not_yet_declared1 | call to not_yet_declared1 |
+| test.c:32:3:32:19 | call to not_yet_declared2 | Function call implicitly declares $@ | test.c:32:3:32:19 | call to not_yet_declared2 | call to not_yet_declared2 |
+| test.c:43:3:43:27 | call to not_declared_defined_with | Function call implicitly declares $@ | test.c:43:3:43:27 | call to not_declared_defined_with | call to not_declared_defined_with |
+| test.c:54:3:54:21 | call to defined_with_double | Function call implicitly declares $@ | test.c:54:3:54:21 | call to defined_with_double | call to defined_with_double |
+| test.c:66:3:66:22 | call to defined_with_ptr_ptr | Function call implicitly declares $@ | test.c:66:3:66:22 | call to defined_with_ptr_ptr | call to defined_with_ptr_ptr |
+| test.c:68:3:68:22 | call to defined_with_ptr_arr | Function call implicitly declares $@ | test.c:68:3:68:22 | call to defined_with_ptr_arr | call to defined_with_ptr_arr |
+| test.c:132:3:132:22 | call to implicit_declaration | Function call implicitly declares $@ | test.c:132:3:132:22 | call to implicit_declaration | call to implicit_declaration |
+| test.c:133:3:133:30 | call to implicit_declaration_k_and_r | Function call implicitly declares $@ | test.c:133:3:133:30 | call to implicit_declaration_k_and_r | call to implicit_declaration_k_and_r |

cpp/ql/test/query-tests/Likely Bugs/Underspecified Functions/ImplicitFunctionDeclaration.qlref

@@ -0,0 +1 @@
+Likely Bugs/Underspecified Functions/ImplicitFunctionDeclaration.ql

cpp/ql/test/query-tests/Likely Bugs/Underspecified Functions/MistypedFunctionArguments.expected

@@ -18,3 +18,4 @@
 | test.c:58:3:58:24 | call to defined_with_long_long | Calling $@: argument $@ of type $@ is incompatible with parameter $@. | test.c:103:11:103:32 | defined_with_long_long | defined_with_long_long | test.c:58:26:58:26 | 3 | 3 | file://:0:0:0:0 | int | int | test.c:103:44:103:45 | ll | long long ll |
 | test.c:60:3:60:21 | call to defined_with_double | Calling $@: argument $@ of type $@ is incompatible with parameter $@. | test.c:99:8:99:26 | defined_with_double | defined_with_double | test.c:60:23:60:25 | 2 | 2 | file://:0:0:0:0 | long long | long long | test.c:99:35:99:35 | d | double d |
 | test.c:61:3:61:24 | call to defined_with_long_long | Calling $@: argument $@ of type $@ is incompatible with parameter $@. | test.c:103:11:103:32 | defined_with_long_long | defined_with_long_long | test.c:61:26:61:31 | 3500000000000000.0 | 3500000000000000.0 | file://:0:0:0:0 | double | double | test.c:103:44:103:45 | ll | long long ll |
+| test.c:137:3:137:27 | call to implicit_declaration_good | Calling $@: argument $@ of type $@ is incompatible with parameter $@. | test2.c:8:6:8:30 | implicit_declaration_good | implicit_declaration_good | test.c:137:35:137:38 | 2.0 | 2.0 | file://:0:0:0:0 | float | float | test2.c:8:52:8:52 | f | float f |

cpp/ql/test/query-tests/Likely Bugs/Underspecified Functions/test.c

@@ -25,11 +25,11 @@ void test(int *argv[]) {
   declared_void(); // GOOD
   declared_with(1); // GOOD
   
-  undeclared();  // GOOD
+  undeclared();  // BAD (GOOD for everything except cpp/implicit-function-declaration)
   undeclared(1); // GOOD
   
-  not_yet_declared1(1); // GOOD
-  not_yet_declared2(1); // GOOD
+  not_yet_declared1(1); // BAD (GOOD for everything except for cpp/implicit-function-declaration)
+  not_yet_declared2(1); // BAD (GOOD for everything except for cpp/implicit-function-declaration)
   not_yet_declared2(ca); // BAD
   not_yet_declared2(); // BAD
 
@@ -40,7 +40,7 @@ void test(int *argv[]) {
   declared_empty_defined_with(&x); // BAD
   declared_empty_defined_with(3, &x); // BAD
 
-  not_declared_defined_with(-1, 0, 2U); // GOOD
+  not_declared_defined_with(-1, 0, 2U); // BAD (GOOD for everything except for cpp/implicit-function-declaration)
   not_declared_defined_with(4LL, 0, 2.5e9f); // BAD
 
   declared_with_pointers(pv, ca); // GOOD
@@ -51,7 +51,7 @@ void test(int *argv[]) {
   defined_with_float(2.f);  // BAD
   defined_with_float(2.0);  // BAD
   
-  defined_with_double(2.f); // GOOD
+  defined_with_double(2.f); // BAD (GOOD for everything except for cpp/implicit-function-declaration)
   defined_with_double('c');  // BAD
   
   defined_with_long_long('c');  // BAD
@@ -63,9 +63,9 @@ void test(int *argv[]) {
   k_and_r_func(2.5, &s);  // GOOD
   
   int (*parameterName)[2];
-  defined_with_ptr_ptr(parameterName); // GOOD
+  defined_with_ptr_ptr(parameterName); // // BAD (GOOD for everything except for cpp/implicit-function-declaration)
   defined_with_ptr_ptr(argv);   // GOOD
-  defined_with_ptr_arr(parameterName); // GOOD
+  defined_with_ptr_arr(parameterName); // // BAD (GOOD for everything except for cpp/implicit-function-declaration)
   defined_with_ptr_arr(argv);   // GOOD
 
   declared_and_defined_empty(); // GOOD
@@ -124,3 +124,17 @@ int call_k_and_r(int i) {
 int will_be_k_and_r(val)
   int val;
 { return val + 1; }
+
+extern int extern_definition(double, double*);
+
+void test_implicit_function_declaration(int x, double d) {
+  int y;
+  implicit_declaration(1, 2); // BAD
+  implicit_declaration_k_and_r(1, 2); // BAD
+
+  implicit_declaration(1, 2); // GOOD (no longer an implicit declaration)
+
+  implicit_declaration_good(1, x, 2.0f); // BAD
+
+  y = extern_definition(3.0f, &d); // GOOD
+}

cpp/ql/test/query-tests/Likely Bugs/Underspecified Functions/test2.c

@@ -0,0 +1,10 @@
+void implicit_declaration(int x) {}
+
+int implicit_declaration_k_and_r(x) int x;
+{
+    return x;
+}
+
+void implicit_declaration_good(int x, int y, float f)
+{
+}