Fix a race condition diagnosed by gcc -Wsequence-point (Bug#8254).

An expression of the form (DOWNCASE (x) == DOWNCASE (y)), found in
dired.c's scmp function, had undefined behavior.
* lisp.h (DOWNCASE_TABLE, UPCASE_TABLE, DOWNCASE, UPPERCASEP):
(NOCASEP, LOWERCASEP, UPCASE, UPCASE1): Move from here ...
* buffer.h: ... to here, because these macros use current_buffer,
and the new implementation with inline functions needs to have
current_buffer in scope now, rather than later when the macros
are used.
(downcase, upcase1): New static inline functions.
(DOWNCASE, UPCASE1): Reimplement using these functions.
This avoids undefined behavior in expressions like
DOWNCASE (x) == DOWNCASE (y), which previously suffered
from race conditions in accessing the global variables
case_temp1 and case_temp2.
* casetab.c (case_temp1, case_temp2): Remove; no longer needed.
* lisp.h (case_temp1, case_temp2): Remove their decls.
* character.h (ASCII_CHAR_P): Move from here ...
* lisp.h: ... to here, so that the inline functions mentioned
above can use them.

1 files changed, 0 insertions, 3 deletions

diff --git a/src/character.h b/src/character.h
index d29ab41557b..6d5b8110109 100644
--- a/src/character.h
+++ b/src/character.h
@@ -128,9 +128,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
     XSETCDR ((x), tmp);                 \
   } while (0)
 
-/* Nonzero iff C is an ASCII character.  */
-#define ASCII_CHAR_P(c) ((unsigned) (c) < 0x80)
-
 /* Nonzero iff C is a character of code less than 0x100.  */
 #define SINGLE_BYTE_CHAR_P(c) ((unsigned) (c) < 0x100)