From: Nicolai Stange <nicstange@xxxxxxxxx>
According to 6.6(9), an address constant may get created by casting
an integer constant to pointer type.
Make evaluate_cast() handle this case, that is tag a cast expression
as being an address constant if the target is a integer constant and
the destination is of pointer type.
Signed-off-by: Nicolai Stange <nicstange@xxxxxxxxx>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
evaluate.c | 7 +++++++
validation/constexpr-pointer-cast.c | 13 +++++++++++++
2 files changed, 20 insertions(+)
create mode 100644 validation/constexpr-pointer-cast.c
diff --git a/evaluate.c b/evaluate.c
index c111f6d19..ce2e52e15 100644
--- a/evaluate.c
+++ b/evaluate.c
@@ -2760,6 +2760,13 @@ static int cast_flags(struct expression *expr, struct expression *old)
*/
else if (old->flags & CEF_FLOAT)
flags = CEF_SET_ICE;
+ } else if (class & TYPE_PTR) {
+ /*
+ * Casts of integer literals to pointer type yield
+ * address constants [6.6(9)].
+ */
+ if (old->flags & CEF_INT)
+ flags = CEF_ADDR;
}
return flags;
diff --git a/validation/constexpr-pointer-cast.c b/validation/constexpr-pointer-cast.c
new file mode 100644
index 000000000..d19c10828
--- /dev/null
+++ b/validation/constexpr-pointer-cast.c
@@ -0,0 +1,13 @@
+static int *a = (int*)0; // OK
+static int b = 0;
+static int *c = (int*)b; // KO
+
+
+/*
+ * check-name: integer literal cast to pointer type constness verification.
+ * check-command: sparse -Wconstexpr-not-const $file
+ *
+ * check-error-start
+constexpr-pointer-cast.c:3:18: warning: non-constant initializer for static object
+ * check-error-end
+ */
--
2.12.0
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