[PATCH v2 2/5] qemu/qarray.h: check scalar type in QARRAY_CREATE()

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

Make sure at compile time that the scalar type of the array
requested to be created via QARRAY_CREATE() matches the scalar
type of the passed auto reference variable (unique pointer).

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
---
 include/qemu/qarray.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/qemu/qarray.h b/include/qemu/qarray.h
index 9885e5e9ed..643c8877c5 100644
--- a/include/qemu/qarray.h
+++ b/include/qemu/qarray.h
@@ -27,6 +27,8 @@
 #ifndef QEMU_QARRAY_H
 #define QEMU_QARRAY_H
 
+#include "qemu/compiler.h"
+
 /**
  * QArray provides a mechanism to access arrays in common C-style (e.g. by
  * square bracket [] operator) in conjunction with reference variables that
@@ -145,6 +147,10 @@
  * @param len - amount of array elements to be allocated immediately
  */
 #define QARRAY_CREATE(scalar_type, auto_var, len) \
+    QEMU_BUILD_BUG_MSG( \
+        !__builtin_types_compatible_p(scalar_type, typeof(*auto_var)), \
+        "QArray scalar type mismatch" \
+    ); \
     qarray_create_##scalar_type((&auto_var), len)
 
 #endif /* QEMU_QARRAY_H */
-- 
2.20.1