Add support for -Wchar-subscripts. Fixes PR4801.

llvm-svn: 81747

2 files changed, 52 insertions, 0 deletions

diff --git a/clang/test/Sema/warn-char-subscripts.c b/clang/test/Sema/warn-char-subscripts.c
new file mode 100644
index 00000000000..65a34e8fc25
--- /dev/null
+++ b/clang/test/Sema/warn-char-subscripts.c
@@ -0,0 +1,31 @@
+// RUN: clang-cc -Wchar-subscripts -fsyntax-only -verify %s
+
+void t1() {
+  int array[1] = { 0 };
+  char subscript = 0;
+  int val = array[subscript]; // expected-warning{{array subscript is of type 'char'}}
+}
+
+void t2() {
+  int array[1] = { 0 };
+  char subscript = 0;
+  int val = subscript[array]; // expected-warning{{array subscript is of type 'char'}}
+}
+
+void t3() {
+  int *array = 0;
+  char subscript = 0;
+  int val = array[subscript]; // expected-warning{{array subscript is of type 'char'}}
+}
+
+void t4() {
+  int *array = 0;
+  char subscript = 0;
+  int val = subscript[array]; // expected-warning{{array subscript is of type 'char'}}
+}
+
+char returnsChar();
+void t5() {
+  int *array = 0;
+  int val = array[returnsChar()]; // expected-warning{{array subscript is of type 'char'}}
+}
diff --git a/clang/test/SemaCXX/warn-char-subscripts.cpp b/clang/test/SemaCXX/warn-char-subscripts.cpp
new file mode 100644
index 00000000000..1c06db91c3f
--- /dev/null
+++ b/clang/test/SemaCXX/warn-char-subscripts.cpp
@@ -0,0 +1,21 @@
+// RUN: clang-cc -Wchar-subscripts -fsyntax-only -verify %s
+
+template<typename T>
+void t1() {
+  int array[1] = { 0 };
+  T subscript = 0;
+  int val = array[subscript]; // expected-warning{{array subscript is of type 'char'}}
+}
+
+template<typename T>
+void t2() {
+  int array[1] = { 0 };
+  T subscript = 0;
+  int val = subscript[array]; // expected-warning{{array subscript is of type 'char'}}
+}
+
+void test() {
+  t1<char>(); // expected-note {{in instantiation of function template specialization 't1<char>' requested here}}
+  t2<char>(); // expected-note {{in instantiation of function template specialization 't2<char>' requested here}}
+}
+