[Bug libfortran/66650] libgfortran: warning: left shift of negative value [-Wshift-negative-value]

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66650

--- Comment #2 from Uroš Bizjak <ubizjak at gmail dot com> ---
Patch that rewrites GFC_DTYPE_SIZE_MASK definition to avoid "left shift of
negative value" warning:

--cut here--
Index: libgfortran.h
===================================================================
--- libgfortran.h       (revision 226339)
+++ libgfortran.h       (working copy)
@@ -404,8 +404,7 @@

 /* Macros to get both the size and the type with a single masking operation 
*/

-#define GFC_DTYPE_SIZE_MASK \
-  ((~((index_type) 0) >> GFC_DTYPE_SIZE_SHIFT) << GFC_DTYPE_SIZE_SHIFT)
+#define GFC_DTYPE_SIZE_MASK (-((index_type) 1 << GFC_DTYPE_SIZE_SHIFT))
 #define GFC_DTYPE_TYPE_SIZE_MASK (GFC_DTYPE_SIZE_MASK | GFC_DTYPE_TYPE_MASK)

 #define GFC_DTYPE_TYPE_SIZE(desc) ((desc)->dtype & GFC_DTYPE_TYPE_SIZE_MASK)
--cut here--