bug#32086: 26.1.50; Floating point exceptions during byte-compilation on alpha-unknown-linux-gnu

[Ulrich Mueller <ulm@gentoo.org>]

Another regression on alpha-unknown-linux-gnu, byte-compilation of the
following four lisp files fails with floating point exceptions:

make[2]: Entering directory '/space/homedirs/ulm/emacs/lisp'
EMACSLOADPATH= '../src/emacs' -batch --no-site-file --no-site-lisp --eval '(setq load-prefer-newer t)'  -f batch-byte-compile calculator.el
EMACSLOADPATH= '../src/emacs' -batch --no-site-file --no-site-lisp --eval '(setq load-prefer-newer t)'  -f batch-byte-compile calc/calc-math.el
EMACSLOADPATH= '../src/emacs' -batch --no-site-file --no-site-lisp --eval '(setq load-prefer-newer t)'  -f batch-byte-compile nxml/rng-xsd.el
EMACSLOADPATH= '../src/emacs' -batch --no-site-file --no-site-lisp --eval '(setq load-prefer-newer t)'  -f batch-byte-compile org/org-table.el
make[2]: *** [Makefile:297: calc/calc-math.elc] Floating point exception
make[2]: *** Waiting for unfinished jobs....
make[2]: *** [Makefile:297: nxml/rng-xsd.elc] Floating point exception
make[2]: *** [Makefile:297: calculator.elc] Floating point exception
make[2]: *** [Makefile:297: org/org-table.elc] Floating point exception
make[2]: Leaving directory '/space/homedirs/ulm/emacs/lisp'
make[1]: *** [Makefile:320: compile-main] Error 2
make[1]: Leaving directory '/space/homedirs/ulm/emacs/lisp'
make: *** [Makefile:405: lisp] Error 2

The exceptions are triggered in functions string_to_number in lread.c
and float_to_string in print.c when values of infinity or NaN are
being passed.

The same lisp files (from the emacs-26 branch) can be compiled with
Emacs 25.3, though.

(On first glance, it doesn't look like the code in lread.c and print.c
has changed, so the problem must be somewhere else. Signal handling?)


In GNU Emacs 26.1.50 (build 1, alpha-unknown-linux-gnu)
 of 2018-07-07 built on monolith
Repository revision: b73cde5e2815c531df7f5fd13e214a7d92f78239

Configured using:
 'configure --prefix=/usr --build=alpha-unknown-linux-gnu
 --host=alpha-unknown-linux-gnu --mandir=/usr/share/man
 --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc
 --localstatedir=/var/lib --disable-silent-rules
 --docdir=/usr/share/doc/emacs-26.1
 --htmldir=/usr/share/doc/emacs-26.1/html --libdir=/usr/lib
 --program-suffix=-emacs-26 --infodir=/usr/share/info/emacs-26
 --localstatedir=/var
 --enable-locallisppath=/etc/emacs:/usr/share/emacs/site-lisp
 --without-compress-install --without-hesiod --without-pop
 --with-file-notification=inotify --enable-acl --without-dbus
 --without-modules --without-gameuser --without-gpm --without-kerberos
 --without-kerberos5 --without-lcms2 --without-xml2 --without-mailutils
 --without-selinux --with-gnutls --without-libsystemd --with-threads
 --without-wide-int --with-zlib --with-sound=no --without-x
 --without-ns'

Configured features:
NOTIFY ACL GNUTLS ZLIB THREADS