Commit 36adc7cd authored by Nick Mathewson's avatar Nick Mathewson 🦀
Browse files

r8844@totoro: nickm | 2006-10-02 16:32:44 -0400 

 Resolve an XXXX: make sure that we are actually on 2s-complement hardware.


svn:r8576
parent 14f9b537

configure.in

+21 −0
Original line number Diff line number Diff line
@@ -588,6 +588,27 @@ if test $tor_cv_malloc_zero_works = yes; then 
            [Define to 1 iff malloc(0) returns a pointer])

fi



# whether we seem to be in a 2s-complement world.

if test -z "$CROSS_COMPILE"; then

AC_CACHE_CHECK([whether we are using 2s-complement arithmetic], tor_cv_twos_complement,

[AC_RUN_IFELSE([AC_LANG_SOURCE(

[[int main () { int problem = ((-99) != (~99)+1);

return problem ? 1 : 0; }]])],

       [tor_cv_twos_complement=yes],

       [tor_cv_twos_complement=no],

       [tor_cv_twos_complement=cross])])



else

  # Cross-compiling; let's hope that the target isn't raving mad.

  AC_MSG_NOTICE([Cross-compiling: we'll assume that NULL is represented as a sequence of 0-valued bytes.])

  tor_cv_twos_complement=yes

fi



if test $tor_cv_twos_complement = yes; then

  AC_DEFINE([USING_TWOS_COMPLEMENT], 1,

            [Define to 1 iff we represent negative integers with two's complement])

fi



# Whether we should use the dmalloc memory allocation debugging library.

AC_MSG_CHECKING(whether to use dmalloc (debug memory allocation library))

AC_ARG_WITH(dmalloc,

src/common/torint.h

+6 −3
Original line number Diff line number Diff line
@@ -220,9 +220,12 @@ typedef uint32_t uintptr_t; 
#error "Missing type uint64_t"

#endif



/* XXXX This assumes a sane (2's-complement) representation.  But if you

/* This assumes a sane (2's-complement) representation.  But if you

 * aren't 2's complement, and you don't define LONG_MAX, then you're so

 * bizarre that I want nothing to do with you. */

#ifndef USING_TWOS_COMPLEMENT

#error "Seems that your platform doesn't use 2's complement arithmetic. Argh."

#endif

#ifndef LONG_MAX

#if (SIZEOF_LONG == 4)

#define LONG_MAX 0x7fffffffL