diff options
Diffstat (limited to 'src/data.c')
| -rw-r--r-- | src/data.c | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/src/data.c b/src/data.c index 577ae777d8..073fb0d492 100644 --- a/src/data.c +++ b/src/data.c @@ -22,6 +22,9 @@ along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ #include <signal.h> #include <stdio.h> #include <setjmp.h> + +#include <intprops.h> + #include "lisp.h" #include "puresize.h" #include "character.h" @@ -2431,6 +2434,10 @@ arith_driver (enum arithop code, size_t nargs, register Lisp_Object *args) register EMACS_INT accum = 0; register EMACS_INT next; + int overflow = 0; + size_t ok_args; + EMACS_INT ok_accum; + switch (SWITCH_ENUM_CAST (code)) { case Alogior: @@ -2451,25 +2458,47 @@ arith_driver (enum arithop code, size_t nargs, register Lisp_Object *args) for (argnum = 0; argnum < nargs; argnum++) { + if (! overflow) + { + ok_args = argnum; + ok_accum = accum; + } + /* Using args[argnum] as argument to CHECK_NUMBER_... */ val = args[argnum]; CHECK_NUMBER_OR_FLOAT_COERCE_MARKER (val); if (FLOATP (val)) - return float_arith_driver ((double) accum, argnum, code, + return float_arith_driver (ok_accum, ok_args, code, nargs, args); args[argnum] = val; next = XINT (args[argnum]); switch (SWITCH_ENUM_CAST (code)) { case Aadd: + if (INT_ADD_OVERFLOW (accum, next)) + { + overflow = 1; + accum &= INTMASK; + } accum += next; break; case Asub: + if (INT_SUBTRACT_OVERFLOW (accum, next)) + { + overflow = 1; + accum &= INTMASK; + } accum = argnum ? accum - next : nargs == 1 ? - next : next; break; case Amult: - accum *= next; + if (INT_MULTIPLY_OVERFLOW (accum, next)) + { + overflow = 1; + accum = (EMACS_UINT) accum * (EMACS_UINT) next & INTMASK; + } + else + accum *= next; break; case Adiv: if (!argnum) @@ -2501,6 +2530,9 @@ arith_driver (enum arithop code, size_t nargs, register Lisp_Object *args) } } + accum &= INTMASK; + if (MOST_POSITIVE_FIXNUM < accum) + accum += MOST_NEGATIVE_FIXNUM - (MOST_POSITIVE_FIXNUM + 1); XSETINT (val, accum); return val; } |