Commit 6df4097e authored by Paul Eggert's avatar Paul Eggert
Browse files

* lisp.h: Redo flags and XSET slightly to avoid overflow diagnostics.

These changes make compilation easier to follow with Sun cc.
(ARRAY_MARK_FLAG): Make it signed, so that it can be assigned to
EMACS_INT values without provoking overflow diagnostics.
(PSEUDOVECTOR_FLAG): Likewise, for consistency.
(XSET) [! USE_LSB_TAG]: Use unsigned left shift to avoid overflow
diagnostic with signed left shift.
parent 410ed5c3
2011-01-17 Paul Eggert <eggert@cs.ucla.edu>
 
* lisp.h: Redo flags and XSET slightly to avoid overflow diagnostics.
These changes make compilation easier to follow with Sun cc.
(ARRAY_MARK_FLAG): Make it signed, so that it can be assigned to
EMACS_INT values without provoking overflow diagnostics.
(PSEUDOVECTOR_FLAG): Likewise, for consistency.
(XSET) [! USE_LSB_TAG]: Use unsigned left shift to avoid overflow
diagnostic with signed left shift.
* fileio.c (make_temp_name): Remove unreachable code.
 
* fontset.c (free_realized_fontset): Mark unreachable code with if (0).
......
......@@ -327,13 +327,14 @@ typedef EMACS_INT Lisp_Object;
#define LISP_MAKE_RVALUE(o) (0+(o))
#endif /* USE_LISP_UNION_TYPE */
/* In the size word of a vector, this bit means the vector has been marked. */
/* In the size word of a vector, this bit means the vector has been marked.
(Shift -1 left, not 1, to avoid provoking overflow diagnostics.) */
#define ARRAY_MARK_FLAG ((EMACS_UINT) 1 << (BITS_PER_EMACS_INT - 1))
#define ARRAY_MARK_FLAG ((EMACS_INT) -1 << (BITS_PER_EMACS_INT - 1))
/* In the size word of a struct Lisp_Vector, this bit means it's really
some other vector-like object. */
#define PSEUDOVECTOR_FLAG ((ARRAY_MARK_FLAG >> 1))
#define PSEUDOVECTOR_FLAG ((EMACS_INT) 1 << (BITS_PER_EMACS_INT - 2))
/* In a pseudovector, the size field actually contains a word with one
PSEUDOVECTOR_FLAG bit set, and exactly one of the following bits to
......@@ -437,8 +438,9 @@ enum pvec_type
((((EMACS_INT) (N)) & VALMASK) | ((EMACS_INT) Lisp_Int) << VALBITS)
#endif
#define XSET(var, type, ptr) \
((var) = ((EMACS_INT)(type) << VALBITS) + ((EMACS_INT) (ptr) & VALMASK))
#define XSET(var, type, ptr) \
((var) = ((EMACS_INT) ((EMACS_UINT) (type) << VALBITS) \
+ ((EMACS_INT) (ptr) & VALMASK)))
#define XPNTR(a) ((EMACS_UINT) ((a) & VALMASK))
......@@ -3670,4 +3672,3 @@ extern Lisp_Object safe_alloca_unwind (Lisp_Object);
#endif /* EMACS_LISP_H */
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment