Implement -Wcast-qual, fixing #13772.

Many thanks to dblaikie for his advices and suggestions!

llvm-svn: 222568

1 files changed, 29 insertions, 0 deletions

diff --git a/clang/test/Sema/warn-cast-qual.c b/clang/test/Sema/warn-cast-qual.c
new file mode 100644
index 00000000000..dc11f5717eb
--- /dev/null
+++ b/clang/test/Sema/warn-cast-qual.c
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fsyntax-only -Wcast-qual -verify %s
+
+#include <stdint.h>
+
+void foo() {
+  const char * const ptr = 0;
+  const char * const *ptrptr = 0;
+  char *y = (char *)ptr;	// expected-warning {{cast from 'const char *' to 'char *' drops const qualifier}}
+  char **y1 = (char **)ptrptr;	// expected-warning {{cast from 'const char *const' to 'char *' drops const qualifier}}
+  const char **y2 = (const char **)ptrptr;	// expected-warning {{cast from 'const char *const *' to 'const char **' drops const qualifier}}
+
+  char *z = (char *)(uintptr_t)(const void *)ptr;	// no warning
+  char *z1 = (char *)(const void *)ptr;	// expected-warning {{cast from 'const void *' to 'char *' drops const qualifier}}
+
+  volatile char *vol = 0;
+  char *vol2 = (char *)vol; // expected-warning {{cast from 'volatile char *' to 'char *' drops volatile qualifier}}
+  const volatile char *volc = 0;
+  char *volc2 = (char *)volc; // expected-warning {{cast from 'const volatile char *' to 'char *' drops const and volatile qualifiers}}
+
+  int **intptrptr;
+  const int **intptrptrc = (const int **)intptrptr; // expected-warning {{cast from 'int **' to 'const int **' must have all intermediate pointers const qualified}}
+  volatile int **intptrptrv = (volatile int **)intptrptr; // expected-warning {{cast from 'int **' to 'volatile int **' must have all intermediate pointers const qualified}}
+
+  int *intptr;
+  const int *intptrc = (const int *)intptr;    // no warning
+
+  const char **charptrptrc;
+  char **charptrptr = (char **)charptrptrc; // expected-warning {{cast from 'const char *' to 'char *' drops const qualifier}}
+}