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(_AC_COMPUTE_INT_COMPILE):

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Check for `expr' arithmetic overflow, and for compilation failure,
and invoke a new argument $4 if either is discovered.
This makes _AC_COMPUTE_INT_COMPILE more like _AC_COMPUTE_INT_RUN.
(_AC_COMPUTE_INT): Pass IF-FAILS arg to _AC_COMPUTE_INT_COMPILE.
This commit is contained in:
Paul Eggert 2001-09-30 15:17:25 +00:00
parent a452b6b7e3
commit a95f040b51
1 changed files with 22 additions and 7 deletions
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29
lib/autoconf/general.m4
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@ -2503,10 +2503,10 @@ m4_define([AC_LIBOBJ],
## ----------------------------------- ##
# _AC_COMPUTE_INT_COMPILE(EXPRESSION, VARIABLE, [INCLUDES])
# _AC_COMPUTE_INT_COMPILE(EXPRESSION, VARIABLE, [INCLUDES], [IF-FAILS])
# ---------------------------------------------------------
# Compute the integer EXPRESSION and store the result in the VARIABLE.
# Works OK if cross compiling.
# Works OK if cross compiling, but assumes twos-complement arithmetic.
m4_define([_AC_COMPUTE_INT_COMPILE],
[# Depending upon the size, compute the lo and hi bounds.
AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$3], [($1) >= 0])],
@ -2514,21 +2514,36 @@ AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$3], [($1) >= 0])],
while :; do
AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$3], [($1) <= $ac_mid])],
[ac_hi=$ac_mid; break],
[ac_lo=`expr $ac_mid + 1`; ac_mid=`expr 2 '*' $ac_mid + 1`])
[ac_lo=`expr $ac_mid + 1`
if test $ac_lo -le $ac_mid; then
ac_lo= ac_hi=
break
fi
ac_mid=`expr 2 '*' $ac_mid + 1`])
done],
[AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$3], [($1) < 0])],
[ac_hi=-1 ac_mid=-1
while :; do
AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$3], [($1) >= $ac_mid])],
[ac_lo=$ac_mid; break],
[ac_hi=`expr '(' $ac_mid ')' - 1`; ac_mid=`expr 2 '*' $ac_mid`])
done])
[ac_hi=`expr '(' $ac_mid ')' - 1`
if test $ac_mid -le $ac_hi; then
ac_lo= ac_hi=
break
fi
ac_mid=`expr 2 '*' $ac_mid`])
done],
[ac_lo= ac_hi=])])
# Binary search between lo and hi bounds.
while test "x$ac_lo" != "x$ac_hi"; do
ac_mid=`expr '(' $ac_hi - $ac_lo ')' / 2 + $ac_lo`
AC_COMPILE_IFELSE([AC_LANG_BOOL_COMPILE_TRY([$3], [($1) <= $ac_mid])],
[ac_hi=$ac_mid], [ac_lo=`expr '(' $ac_mid ')' + 1`])
done
$2=$ac_lo[]dnl
case $ac_lo in
?*) $2=$ac_lo;;
'') $4 ;;
esac[]dnl
])# _AC_COMPUTE_INT_COMPILE
@ -2544,7 +2559,7 @@ m4_define([_AC_COMPUTE_INT_RUN],
# ---------------------------------------------------------
m4_define([_AC_COMPUTE_INT],
[if test "$cross_compiling" = yes; then
_AC_COMPUTE_INT_COMPILE([$1], [$2], [$3])
_AC_COMPUTE_INT_COMPILE([$1], [$2], [$3], [$4])
else
_AC_COMPUTE_INT_RUN([$1], [$2], [$3], [$4])
fi