Re: lynx-dev lynx --enable-color-style causes fp error

[Stanislav Brabec]

Hallo Larry W. Virden,

sorry for not explaining lynx bug in details, I didn't know if this
experimental feature isn't broken.

Lynx crashes whenever --enable-color-style and curses COLORS==0.

I was done some tracing with TERM=xterm (from ncurses-4.2 terminfo database).
There is defined no color support and it causes lynx 2.8 to hang (see gdb 
output).
The same code works OK with xfree-3.3.2 terminfo.


This works:
configure --prefix=/usr --with-screen=slang --enable-8bit-toupper 
--enable-default-colors \
--enable-externs --enable-font-switch --enable-internal-links --enable-nsl-fork 
\
--enable-underlines --with-zlib

This is buggy:
configure --prefix=/usr --enable-color-style --enable-debug

For this test I have removed -O2 from makefiles:
sedfile s/-O2//g makefile */makefile */*/makefile */*/*/makefile

-------------------------------------------------------------

exception in: src/LYStyle.c
*************************************************************
    bA = check_color(bg, default_bg);
    if (fA == NO_COLOR) {
        bA = NO_COLOR;
    } else {
        if (fA >= COLORS || bA >= COLORS)
            cA = A_BOLD;
        if (fA >= COLORS)
->          fA %= COLORS;
        if (bA > COLORS)
            bA %= COLORS;
    }

    /*
     * If we have colour, and space to create a new colour attribute,
     * and we have a valid colour description, then add this style
     */
    if (lynx_has_color && colorPairs < COLOR_PAIRS-1 && fA != NO_COLOR)
    {
        if (colorPairs <= 0 || fA != last_fA || bA != last_bA) {
            colorPairs++;
            init_pair(colorPairs, fA, bA);
            last_fA = fA;
            last_bA = bA;
*************************************************************
Program received signal SIGFPE, Arithmetic exception.
0x80d5a14 in parse_attributes (mono=0x81c910f "bold", fg=0x81c9114 "white", 
bg=0x81c911a "green", style=133, element=0x81c9100 "link.green.toc") at 
./LYStyle.c:84
(xxgdb) print COLORS
$1 = 0
(xxgdb) print fA
$2 = 15
(xxgdb) 
---------------------- config.cache -------------------------
# This file is a shell script that caches the results of configure
# tests run on this system so they can be shared between configure
# scripts and configure runs.  It is not useful on other systems.
# If it contains results you don't want to keep, you may remove or edit it.
#
# By default, configure uses ./config.cache as the cache file,
# creating it if it does not exist already.  You can give configure
# the --cache-file=FILE option to use a different cache file; that is
# what configure does when it calls configure scripts in
# subdirectories, so they share the cache.
# Giving --cache-file=/dev/null disables caching, for debugging configure.
# config.status only pays attention to the cache file if you give it the
# --recheck option to rerun configure.
#
ac_cv_c_const=${ac_cv_c_const=yes}
ac_cv_func_cbreak=${ac_cv_func_cbreak=yes}
ac_cv_func_cuserid=${ac_cv_func_cuserid=yes}
ac_cv_func_decl_getgrgid=${ac_cv_func_decl_getgrgid=yes}
ac_cv_func_decl_getgrnam=${ac_cv_func_decl_getgrnam=yes}
ac_cv_func_decl_strstr=${ac_cv_func_decl_strstr=yes}
ac_cv_func_getcwd=${ac_cv_func_getcwd=yes}
ac_cv_func_getgroups=${ac_cv_func_getgroups=yes}
ac_cv_func_gethostbyname=${ac_cv_func_gethostbyname=yes}
ac_cv_func_gethostname=${ac_cv_func_gethostname=yes}
ac_cv_func_initscr=${ac_cv_func_initscr=no}
ac_cv_func_keypad=${ac_cv_func_keypad=yes}
ac_cv_func_lstat=${ac_cv_func_lstat=yes}
ac_cv_func_mktime=${ac_cv_func_mktime=yes}
ac_cv_func_putenv=${ac_cv_func_putenv=yes}
ac_cv_func_readdir=${ac_cv_func_readdir=yes}
ac_cv_func_socket=${ac_cv_func_socket=yes}
ac_cv_func_strcasecmp=${ac_cv_func_strcasecmp=yes}
ac_cv_func_strerror=${ac_cv_func_strerror=yes}
ac_cv_func_strstr=${ac_cv_func_strstr=yes}
ac_cv_func_tgoto=${ac_cv_func_tgoto=no}
ac_cv_func_use_default_colors=${ac_cv_func_use_default_colors=yes}
ac_cv_func_vfork_works=${ac_cv_func_vfork_works=yes}
ac_cv_func_waitpid=${ac_cv_func_waitpid=yes}
ac_cv_func_wborder=${ac_cv_func_wborder=yes}
ac_cv_header_dirent_dirent_h=${ac_cv_header_dirent_dirent_h=yes}
ac_cv_header_fcntl_h=${ac_cv_header_fcntl_h=yes}
ac_cv_header_limits_h=${ac_cv_header_limits_h=yes}
ac_cv_header_stdc=${ac_cv_header_stdc=yes}
ac_cv_header_stdlib_h=${ac_cv_header_stdlib_h=yes}
ac_cv_header_string_h=${ac_cv_header_string_h=yes}
ac_cv_header_sys_fcntl_h=${ac_cv_header_sys_fcntl_h=yes}
ac_cv_header_sys_filio_h=${ac_cv_header_sys_filio_h=no}
ac_cv_header_sys_ioctl_h=${ac_cv_header_sys_ioctl_h=yes}
ac_cv_header_sys_param_h=${ac_cv_header_sys_param_h=yes}
ac_cv_header_sys_time_h=${ac_cv_header_sys_time_h=yes}
ac_cv_header_sys_wait_h=${ac_cv_header_sys_wait_h=yes}
ac_cv_header_termio_h=${ac_cv_header_termio_h=yes}
ac_cv_header_termios_h=${ac_cv_header_termios_h=yes}
ac_cv_header_time=${ac_cv_header_time=yes}
ac_cv_header_unistd_h=${ac_cv_header_unistd_h=yes}
ac_cv_header_vfork_h=${ac_cv_header_vfork_h=no}
ac_cv_lib_curses_initscr=${ac_cv_lib_curses_initscr=yes}
ac_cv_lib_dir_opendir=${ac_cv_lib_dir_opendir=no}
ac_cv_lib_inet=${ac_cv_lib_inet=no}
ac_cv_lib_termcap_tgoto=${ac_cv_lib_termcap_tgoto=yes}
ac_cv_path_CHMOD=${ac_cv_path_CHMOD=/bin/chmod}
ac_cv_path_COMPRESS=${ac_cv_path_COMPRESS=/usr/bin/compress}
ac_cv_path_COPY=${ac_cv_path_COPY=/bin/cp}
ac_cv_path_GZIP=${ac_cv_path_GZIP=/bin/gzip}
ac_cv_path_MKDIR=${ac_cv_path_MKDIR=/bin/mkdir}
ac_cv_path_MV=${ac_cv_path_MV=/bin/mv}
ac_cv_path_RM=${ac_cv_path_RM=/bin/rm}
ac_cv_path_TAR=${ac_cv_path_TAR=/bin/tar}
ac_cv_path_TOUCH=${ac_cv_path_TOUCH=/bin/touch}
ac_cv_path_UNCOMPRESS=${ac_cv_path_UNCOMPRESS=/bin/gunzip}
ac_cv_path_UNZIP=${ac_cv_path_UNZIP=/usr/bin/unzip}
ac_cv_path_UUDECODE=${ac_cv_path_UUDECODE=/usr/bin/uudecode}
ac_cv_path_ZCAT=${ac_cv_path_ZCAT=/bin/zcat}
ac_cv_path_ZIP=${ac_cv_path_ZIP=/usr/bin/zip}
ac_cv_path_install=${ac_cv_path_install='/bin/ginstall -c'}
ac_cv_prog_CC=${ac_cv_prog_CC=gcc}
ac_cv_prog_CPP=${ac_cv_prog_CPP='gcc -E'}
ac_cv_prog_RANLIB=${ac_cv_prog_RANLIB=ranlib}
ac_cv_prog_cc_cross=${ac_cv_prog_cc_cross=no}
ac_cv_prog_cc_g=${ac_cv_prog_cc_g=yes}
ac_cv_prog_cc_works=${ac_cv_prog_cc_works=yes}
ac_cv_prog_gcc=${ac_cv_prog_gcc=yes}
ac_cv_prog_make_make_set=${ac_cv_prog_make_make_set=yes}
ac_cv_type_mode_t=${ac_cv_type_mode_t=yes}
ac_cv_type_pid_t=${ac_cv_type_pid_t=yes}
cf_cv_SYSTEM_MAIL=${cf_cv_SYSTEM_MAIL=/usr/sbin/sendmail}
cf_cv_alt_char_set=${cf_cv_alt_char_set=yes}
cf_cv_baddef_remove=${cf_cv_baddef_remove=no}
cf_cv_bool_defs=${cf_cv_bool_defs=yes}
cf_cv_color_curses=${cf_cv_color_curses=yes}
cf_cv_curs_performance=${cf_cv_curs_performance=no}
cf_cv_dcl_errno=${cf_cv_dcl_errno=yes}
cf_cv_dcl_sys_errlist=${cf_cv_dcl_sys_errlist=yes}
cf_cv_dcl_sys_nerr=${cf_cv_dcl_sys_nerr=yes}
cf_cv_fancy_curses=${cf_cv_fancy_curses=yes}
cf_cv_fionbio=${cf_cv_fionbio=ioctl}
cf_cv_have_errno=${cf_cv_have_errno=yes}
cf_cv_have_sys_errlist=${cf_cv_have_sys_errlist=yes}
cf_cv_have_sys_nerr=${cf_cv_have_sys_nerr=yes}
cf_cv_have_ttytype=${cf_cv_have_ttytype=yes}
cf_cv_have_utmp=${cf_cv_have_utmp=yes}
cf_cv_locale=${cf_cv_locale=yes}
cf_cv_ncurses_broken=${cf_cv_ncurses_broken=no}
cf_cv_ncurses_header=${cf_cv_ncurses_header=curses.h}
cf_cv_ncurses_version=${cf_cv_ncurses_version=4.2.980228}
cf_cv_netlibs=${cf_cv_netlibs=}
cf_cv_ngroups=${cf_cv_ngroups=yes}
cf_cv_screen=${cf_cv_screen=curses}
cf_cv_sizechange=${cf_cv_sizechange=yes}
cf_cv_system_mail_flags=${cf_cv_system_mail_flags='-t -oi'}
cf_cv_termio_and_termios=${cf_cv_termio_and_termios=yes}
cf_cv_type_unionwait=${cf_cv_type_unionwait=no}
-------------------------------------------------------------
Note:
configure --prefix=/usr --with-screen=slang --enable-8bit-toupper 
--enable-default-colors --enable-externs --enable-font-switch 
--enable-internal-links --enable-nsl-fork --enable-underlines --with-zlib 
--enable-color-style
returns also
checking if color-style code should be used... configure: error: Configuration 
does not support color-styles

-- Stanislav Brabec