Port to GCC 7

Or, more accurately, to any system that #defines CHAR_WIDTH
to something else.  Do not merge to master.
* src/character.h (CHAR_WIDTH): Undef before defining.

diff --git a/src/character.h b/src/character.h
index a94ec6d22dd7e6eab912d1be5514a84c07102138..18f04573516abd843c129d5be52cadd0b67033a6 100644 (file)
--- a/src/character.h
+++ b/src/character.h
@@ -590,6 +590,7 @@ sanitize_char_width (EMACS_INT width)
    columns C will occupy on the screen when displayed in the current
    buffer.  */
 
+#undef CHAR_WIDTH /* in case system headers follow ISO/IEC TS 18661-1:2014 */
 #define CHAR_WIDTH(c)          \
   (ASCII_CHAR_P (c)            \
    ? ASCII_CHAR_WIDTH (c)      \