aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/validation/linear/struct-init-full.c
diff options
authorLuc Van Oostenryck <luc.vanoostenryck@gmail.com>2017-04-06 15:50:23 +0200
committerLuc Van Oostenryck <luc.vanoostenryck@gmail.com>2017-05-19 05:35:01 +0200
commitb1672eab399fdce2c050e8aa07767489a2071981 (patch)
tree7a7edd535f4747c5e8f84dc6f1ab3181e50746a3 /validation/linear/struct-init-full.c
parent816e13f57644116daf20debe548e3e53ec4e5073 (diff)
downloadsparse-dev-b1672eab399fdce2c050e8aa07767489a2071981.tar.gz
fix implicit zero initializer.
The C standard requires that, when initializing an aggregate, all fieds not explicitly initialized shall be implicity zero-initialized (more exactly "the same as objects that have static storage duration" [6.7.9.21]). Until now sparse didn't did this. Fix this (when an initializer is present and the object not a scalar) by first storing zeroes in the whole object before doing the initialization of each fields explicitly initialized. Note 1: this patch initialize the *whole* aggregate while the standard only requires that existing fields are initialized. Thanks to Linus to notice this. Note 2: this implicit initialization is not needed if all fields are explicitly initialized but is done anyway, for the moment. Note 3: the code simplify nicely when there is a single field that is initialized, much less so when there is several ones. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Diffstat (limited to 'validation/linear/struct-init-full.c')
-rw-r--r--validation/linear/struct-init-full.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/validation/linear/struct-init-full.c b/validation/linear/struct-init-full.c
new file mode 100644
index 00000000..f1b03db7
--- /dev/null
+++ b/validation/linear/struct-init-full.c
@@ -0,0 +1,28 @@
+struct s {
+ int a, b, c;
+};
+
+struct s s_init_all(int a)
+{
+ struct s s = { .a = a, .b = 42, .c = 123, };
+ return s;
+}
+
+/*
+ * check-name: struct implicit init zero not needed
+ * check-command: test-linearize -Wno-decl $file
+ * check-known-to-fail
+ *
+ * check-output-start
+s_init_all:
+.L4:
+ <entry-point>
+ store.32 %arg1 -> 0[s]
+ store.32 $42 -> 4[s]
+ store.32 $123 -> 8[s]
+ load.96 %r8 <- 0[s]
+ ret.96 %r8
+
+
+ * check-output-end
+ */