Implement -Wcast-align. The initial design of this diagnostic diverges
from GCC's in that we warn on *any* increase in alignment requirements, not
just those that are enforced by hardware. Please let us know if this causes
major problems for you (which it shouldn't, since it's an optional warning).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@110959 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Sema/warn-cast-align.c b/test/Sema/warn-cast-align.c
new file mode 100644
index 0000000..11e3c41
--- /dev/null
+++ b/test/Sema/warn-cast-align.c
@@ -0,0 +1,41 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fsyntax-only -Wcast-align -verify %s
+
+// Simple casts.
+void test0(char *P) {
+ char *a = (char*) P;
+ short *b = (short*) P; // expected-warning {{cast from 'char *' to 'short *' increases required alignment from 1 to 2}}
+ int *c = (int*) P; // expected-warning {{cast from 'char *' to 'int *' increases required alignment from 1 to 4}}
+}
+
+// Casts from void* are a special case.
+void test1(void *P) {
+ char *a = (char*) P;
+ short *b = (short*) P;
+ int *c = (int*) P;
+
+ const volatile void *P2 = P;
+ char *d = (char*) P2;
+ short *e = (short*) P2;
+ int *f = (int*) P2;
+
+ const char *g = (const char*) P2;
+ const short *h = (const short*) P2;
+ const int *i = (const int*) P2;
+
+ const volatile char *j = (const volatile char*) P2;
+ const volatile short *k = (const volatile short*) P2;
+ const volatile int *l = (const volatile int*) P2;
+}
+
+// Aligned struct.
+__attribute__((align(16))) struct A {
+ char buffer[16];
+};
+void test2(char *P) {
+ struct A *a = (struct A*) P; // expected-warning {{cast from 'char *' to 'struct A *' increases required alignment from 1 to 16}}
+}
+
+// Incomplete type.
+void test3(char *P) {
+ struct B *b = (struct B*) P;
+}