C++: Support GCC flags making ptr overflow defined

jbj · jbj · commit d2009c53dc9b · 2019-11-13T14:07:33.000+01:00
diff --git a/cpp/ql/src/Likely Bugs/Memory Management/PointerOverflow.ql b/cpp/ql/src/Likely Bugs/Memory Management/PointerOverflow.ql
@@ -25,6 +25,11 @@ where
   not exists(MacroInvocation mi |
     mi.getAnAffectedElement() = add and
     not mi.getMacroName().toLowerCase().matches("%assert%")
+  ) and
+  // There must be a compilation of this file without a flag that makes pointer
+  // overflow well defined.
+  exists(Compilation c | c.getAFileCompiled() = ro.getFile() |
+    not c.getAnArgument() = "-fwrapv-pointer" and
+    not c.getAnArgument() = "-fno-strict-overflow"
   )
-  // TODO: Add a check for -fno-strict-overflow and -fwrapv-pointer
 select ro, "Range check relying on pointer overflow."
diff --git a/cpp/ql/test/query-tests/Likely Bugs/Memory Management/PointerOverflow/PointerOverflow.expected b/cpp/ql/test/query-tests/Likely Bugs/Memory Management/PointerOverflow/PointerOverflow.expected
@@ -1,3 +1,2 @@
-| no_strict_overflow.c:5:9:5:21 | ... < ... | Range check relying on pointer overflow. |
 | test.cpp:6:12:6:33 | ... < ... | Range check relying on pointer overflow. |
 | test.cpp:33:9:33:21 | ... < ... | Range check relying on pointer overflow. |

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,2 @@`
`1`		`-\| no_strict_overflow.c:5:9:5:21 \| ... < ... \| Range check relying on pointer overflow. \|`
`2`	`1`	`\| test.cpp:6:12:6:33 \| ... < ... \| Range check relying on pointer overflow. \|`
`3`	`2`	`\| test.cpp:33:9:33:21 \| ... < ... \| Range check relying on pointer overflow. \|`