2003-10-21 Arnaud Charlet <charlet@act-europe.fr>

	* 3psoccon.ads, 3veacodu.adb, 3vexpect.adb, 3vsoccon.ads,
	3vsocthi.adb, 3vsocthi.ads, 3vtrasym.adb, 3zsoccon.ads,
	3zsocthi.adb, 3zsocthi.ads, 50system.ads, 51system.ads,
	55system.ads, 56osinte.adb, 56osinte.ads, 56taprop.adb,
	56taspri.ads, 56tpopsp.adb, 57system.ads, 58system.ads,
	59system.ads, 5aml-tgt.adb, 5bml-tgt.adb, 5csystem.ads,
	5dsystem.ads, 5fosinte.adb, 5gml-tgt.adb, 5hml-tgt.adb,
	5isystem.ads, 5lparame.adb, 5msystem.ads, 5psystem.ads,
	5sml-tgt.adb, 5sosprim.adb, 5stpopsp.adb, 5tsystem.ads,
	5usystem.ads, 5vml-tgt.adb, 5vsymbol.adb, 5vtraent.adb,
	5vtraent.ads, 5wml-tgt.adb, 5xparame.ads, 5xsystem.ads,
	5xvxwork.ads, 5yparame.ads, 5ytiitho.adb, 5zinit.adb,
	5zml-tgt.adb, 5zparame.ads, 5ztaspri.ads, 5ztfsetr.adb,
	5zthrini.adb, 5ztiitho.adb, 5ztpopsp.adb, 7stfsetr.adb,
	7straces.adb, 7strafor.adb, 7strafor.ads, 7stratas.adb,
	a-excach.adb, a-exexda.adb, a-exexpr.adb, a-exextr.adb,
	a-exstat.adb, a-strsup.adb, a-strsup.ads, a-stwisu.adb,
	a-stwisu.ads, bld.adb, bld.ads, bld-io.adb,
	bld-io.ads, clean.adb, clean.ads, ctrl_c.c,
	erroutc.adb, erroutc.ads, errutil.adb, errutil.ads,
	err_vars.ads, final.c, g-arrspl.adb, g-arrspl.ads,
	g-boubuf.adb, g-boubuf.ads, g-boumai.ads, g-bubsor.adb,
	g-bubsor.ads, g-comver.adb, g-comver.ads, g-ctrl_c.ads,
	g-dynhta.adb, g-dynhta.ads, g-eacodu.adb, g-excact.adb,
	g-excact.ads, g-heasor.adb, g-heasor.ads, g-memdum.adb,
	g-memdum.ads, gnatclean.adb, gnatsym.adb, g-pehage.adb,
	g-pehage.ads, g-perhas.ads, gpr2make.adb, gpr2make.ads,
	gprcmd.adb, gprep.adb, gprep.ads, g-semaph.adb,
	g-semaph.ads, g-string.adb, g-string.ads, g-strspl.ads,
	g-wistsp.ads, i-vthrea.adb, i-vthrea.ads, i-vxwoio.adb,
	i-vxwoio.ads, Makefile.generic, Makefile.prolog, Makefile.rtl,
	prep.adb, prep.ads, prepcomp.adb, prepcomp.ads,
	prj-err.adb, prj-err.ads, s-boarop.ads, s-carsi8.adb,
	s-carsi8.ads, s-carun8.adb, s-carun8.ads, s-casi16.adb,
	s-casi16.ads, s-casi32.adb, s-casi32.ads, s-casi64.adb,
	s-casi64.ads, s-casuti.adb, s-casuti.ads, s-caun16.adb,
	s-caun16.ads, s-caun32.adb, s-caun32.ads, s-caun64.adb,
	s-caun64.ads, scng.adb, scng.ads, s-exnint.adb,
	s-exnllf.adb, s-exnlli.adb, s-expint.adb, s-explli.adb,
	s-geveop.adb, s-geveop.ads, s-hibaen.ads, s-htable.adb,
	s-htable.ads, sinput-c.adb, sinput-c.ads, s-memcop.ads,
	socket.c, s-purexc.ads, s-scaval.adb, s-stopoo.adb,
	s-strcom.adb, s-strcom.ads, s-strxdr.adb, s-rident.ads,
	s-thread.adb, s-thread.ads, s-tpae65.adb, s-tpae65.ads,
	s-tporft.adb, s-traent.adb, s-traent.ads, styleg.adb,
	styleg.ads, styleg-c.adb, styleg-c.ads, s-veboop.adb,
	s-veboop.ads, s-vector.ads, symbols.adb, symbols.ads,
	tb-alvms.c, tb-alvxw.c, tempdir.adb, tempdir.ads,
	vms_conv.ads, vms_conv.adb, vms_data.ads,
	vxaddr2line.adb: Files added. Merge with ACT tree.

	* 4dintnam.ads, 4mintnam.ads, 4uintnam.ads, 52system.ads,
	5dosinte.ads, 5etpopse.adb, 5mosinte.ads, 5qosinte.adb,
	5qosinte.ads, 5qstache.adb, 5qtaprop.adb, 5qtaspri.ads,
	5stpopse.adb, 5uintman.adb, 5uosinte.ads, adafinal.c,
	g-enblsp.adb, io-aux.c, scn-nlit.adb, scn-slit.adb,
	s-exnflt.ads, s-exngen.adb, s-exngen.ads, s-exnlfl.ads,
	s-exnlin.ads, s-exnsfl.ads, s-exnsin.ads, s-exnssi.ads,
	s-expflt.ads, s-expgen.adb, s-expgen.ads, s-explfl.ads,
	s-explin.ads, s-expllf.ads, s-expsfl.ads, s-expsin.ads,
	s-expssi.ads, style.adb: Files removed. Merge with ACT tree.

	* 1ic.ads, 31soccon.ads, 31soliop.ads, 3asoccon.ads,
	3bsoccon.ads, 3gsoccon.ads, 3hsoccon.ads, 3ssoccon.ads,
	3ssoliop.ads, 3wsoccon.ads, 3wsocthi.adb, 3wsocthi.ads,
	3wsoliop.ads, 41intnam.ads, 42intnam.ads, 4aintnam.ads,
	4cintnam.ads, 4gintnam.ads, 4hexcpol.adb, 4hintnam.ads,
	4lintnam.ads, 4nintnam.ads, 4ointnam.ads, 4onumaux.ads,
	4pintnam.ads, 4sintnam.ads, 4vcaldel.adb, 4vcalend.adb,
	4vintnam.ads, 4wexcpol.adb, 4wintnam.ads, 4zintnam.ads,
	51osinte.adb, 51osinte.ads, 52osinte.adb, 52osinte.ads,
	53osinte.ads, 54osinte.ads, 5aosinte.adb, 5aosinte.ads,
	5asystem.ads, 5ataprop.adb, 5atasinf.ads, 5ataspri.ads,
	5atpopsp.adb, 5avxwork.ads, 5bosinte.adb, 5bosinte.ads,
	5bsystem.ads, 5cosinte.ads, 5esystem.ads, 5fintman.adb,
	5fosinte.ads, 5fsystem.ads, 5ftaprop.adb, 5ftasinf.ads,
	5ginterr.adb, 5gintman.adb, 5gmastop.adb, 5gosinte.ads,
	5gproinf.ads, 5gsystem.ads, 5gtaprop.adb, 5gtasinf.ads,
	5gtpgetc.adb, 5hosinte.adb, 5hosinte.ads, 5hsystem.ads,
	5htaprop.adb, 5htaspri.ads, 5htraceb.adb, 5iosinte.adb,
	5itaprop.adb, 5itaspri.ads, 5ksystem.ads, 5kvxwork.ads,
	5lintman.adb, 5lml-tgt.adb, 5losinte.ads, 5lsystem.ads,
	5mvxwork.ads, 5ninmaop.adb, 5nintman.adb, 5nosinte.ads,
	5ntaprop.adb, 5ntaspri.ads, 5ointerr.adb, 5omastop.adb,
	5oosinte.adb, 5oosinte.ads, 5oosprim.adb, 5oparame.adb,
	5osystem.ads, 5otaprop.adb, 5otaspri.ads, 5posinte.ads,
	5posprim.adb, 5pvxwork.ads, 5sintman.adb, 5sosinte.adb,
	5sosinte.ads, 5ssystem.ads, 5staprop.adb, 5stasinf.ads,
	5staspri.ads, 5svxwork.ads, 5tosinte.ads, 5vasthan.adb,
	5vinmaop.adb, 5vinterr.adb, 5vintman.adb, 5vintman.ads,
	5vmastop.adb, 5vosinte.adb, 5vosinte.ads, 5vosprim.adb,
	5vsystem.ads, 5vtaprop.adb, 5vtaspri.ads, 5vtpopde.adb,
	5vtpopde.ads, 5wgloloc.adb, 5wintman.adb, 5wmemory.adb,
	5wosprim.adb, 5wsystem.ads, 5wtaprop.adb, 5wtaspri.ads,
	5ysystem.ads, 5zinterr.adb, 5zintman.adb, 5zosinte.adb,
	5zosinte.ads, 5zosprim.adb, 5zsystem.ads, 5ztaprop.adb,
	6vcpp.adb, 6vcstrea.adb, 6vinterf.ads, 7sinmaop.adb,
	7sintman.adb, 7sosinte.adb, 7sosprim.adb, 7staprop.adb,
	7staspri.ads, 7stpopsp.adb, 7straceb.adb, 9drpc.adb,
	a-caldel.adb, a-caldel.ads, a-charac.ads, a-colien.ads,
	a-comlin.adb, adaint.c, adaint.h, ada-tree.def,
	a-diocst.adb, a-diocst.ads, a-direio.adb, a-except.adb,
	a-except.ads, a-excpol.adb, a-exctra.adb, a-exctra.ads,
	a-filico.adb, a-interr.adb, a-intsig.adb, a-intsig.ads,
	ali.adb, ali.ads, ali-util.adb, ali-util.ads,
	a-ngcefu.adb, a-ngcoty.adb, a-ngelfu.adb, a-nudira.adb,
	a-nudira.ads, a-nuflra.adb, a-nuflra.ads, a-reatim.adb,
	a-reatim.ads, a-retide.ads, a-sequio.adb, a-siocst.adb,
	a-siocst.ads, a-ssicst.adb, a-ssicst.ads, a-strbou.adb,
	a-strbou.ads, a-strfix.adb, a-strmap.adb, a-strsea.ads,
	a-strunb.adb, a-strunb.ads, a-ststio.adb, a-stunau.adb,
	a-stunau.ads, a-stwibo.adb, a-stwibo.ads, a-stwifi.adb,
	a-stwima.adb, a-stwiun.adb, a-stwiun.ads, a-tags.adb,
	a-tags.ads, a-tasatt.adb, a-taside.adb, a-teioed.adb,
	a-textio.adb, a-textio.ads, a-tienau.adb, a-tifiio.adb,
	a-tiflau.adb, a-tiflio.adb, a-tigeau.adb, a-tigeau.ads,
	a-tiinau.adb, a-timoau.adb, a-tiocst.adb, a-tiocst.ads,
	atree.adb, atree.ads, a-witeio.adb, a-witeio.ads,
	a-wtcstr.adb, a-wtcstr.ads, a-wtdeio.adb, a-wtedit.adb,
	a-wtenau.adb, a-wtflau.adb, a-wtinau.adb, a-wtmoau.adb,
	bcheck.adb, binde.adb, bindgen.adb, bindusg.adb,
	checks.adb, checks.ads, cio.c, comperr.adb,
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	einfo.adb, einfo.ads, errout.adb, errout.ads,
	eval_fat.adb, eval_fat.ads, exp_aggr.adb, expander.adb,
	expander.ads, exp_attr.adb, exp_ch11.adb, exp_ch13.adb,
	exp_ch2.adb, exp_ch3.adb, exp_ch3.ads, exp_ch4.adb,
	exp_ch5.adb, exp_ch6.adb, exp_ch7.adb, exp_ch7.ads,
	exp_ch8.adb, exp_ch9.adb, exp_code.adb, exp_dbug.adb,
	exp_dbug.ads, exp_disp.adb, exp_dist.adb, expect.c,
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	exp_prag.adb, exp_strm.adb, exp_strm.ads, exp_tss.adb,
	exp_tss.ads, exp_util.adb, exp_util.ads, exp_vfpt.adb,
	fe.h, fmap.adb, fmap.ads, fname.adb,
	fname.ads, fname-uf.adb, fname-uf.ads, freeze.adb,
	freeze.ads, frontend.adb, g-awk.adb, g-awk.ads,
	g-busora.adb, g-busora.ads, g-busorg.adb, g-busorg.ads,
	g-casuti.adb, g-casuti.ads, g-catiio.adb, g-catiio.ads,
	g-cgi.adb, g-cgi.ads, g-cgicoo.adb, g-cgicoo.ads,
	g-cgideb.adb, g-cgideb.ads, g-comlin.adb, g-comlin.ads,
	g-crc32.adb, g-crc32.ads, g-debpoo.adb, g-debpoo.ads,
	g-debuti.adb, g-debuti.ads, g-diopit.adb, g-diopit.ads,
	g-dirope.adb, g-dirope.ads, g-dyntab.adb, g-dyntab.ads,
	g-except.ads, g-exctra.adb, g-exctra.ads, g-expect.adb,
	g-expect.ads, g-hesora.adb, g-hesora.ads, g-hesorg.adb,
	g-hesorg.ads, g-htable.adb, g-htable.ads, gigi.h,
	g-io.adb, g-io.ads, g-io_aux.adb, g-io_aux.ads,
	g-locfil.adb, g-locfil.ads, g-md5.adb, g-md5.ads,
	gmem.c, gnat1drv.adb, gnatbind.adb, gnatchop.adb,
	gnatcmd.adb, gnatfind.adb, gnatkr.adb, gnatlbr.adb,
	gnatlink.adb, gnatls.adb, gnatmake.adb, gnatmem.adb,
	gnatname.adb, gnatprep.adb, gnatprep.ads, gnatpsta.adb,
	gnatxref.adb, g-os_lib.adb, g-os_lib.ads, g-regexp.adb,
	g-regexp.ads, g-regist.adb, g-regist.ads, g-regpat.adb,
	g-regpat.ads, g-soccon.ads, g-socket.adb, g-socket.ads,
	g-socthi.adb, g-socthi.ads, g-soliop.ads, g-souinf.ads,
	g-speche.adb, g-speche.ads, g-spipat.adb, g-spipat.ads,
	g-spitbo.adb, g-spitbo.ads, g-sptabo.ads, g-sptain.ads,
	g-sptavs.ads, g-table.adb, g-table.ads, g-tasloc.adb,
	g-tasloc.ads, g-thread.adb, g-thread.ads, g-traceb.adb,
	g-traceb.ads, g-trasym.adb, g-trasym.ads, hostparm.ads,
	i-c.ads, i-cobol.adb, i-cpp.adb, i-cstrea.ads,
	i-cstrin.adb, i-cstrin.ads, impunit.adb, init.c,
	inline.adb, interfac.ads, i-pacdec.ads, itypes.adb,
	itypes.ads, i-vxwork.ads, lang.opt, lang-specs.h,
	layout.adb, lib.adb, lib.ads, lib-list.adb,
	lib-load.adb, lib-load.ads, lib-sort.adb, lib-util.adb,
	lib-writ.adb, lib-writ.ads, lib-xref.adb, lib-xref.ads,
	link.c, live.adb, make.adb, make.ads,
	Makefile.adalib, Makefile.in, Make-lang.in, makeusg.adb,
	mdll.adb, mdll-fil.adb, mdll-fil.ads, mdll-utl.adb,
	mdll-utl.ads, memroot.adb, memroot.ads, memtrack.adb,
	misc.c, mkdir.c, mlib.adb, mlib.ads,
	mlib-fil.adb, mlib-fil.ads, mlib-prj.adb, mlib-prj.ads,
	mlib-tgt.adb, mlib-tgt.ads, mlib-utl.adb, mlib-utl.ads,
	namet.adb, namet.ads, namet.h, nlists.ads,
	nlists.h, nmake.adt, opt.adb, opt.ads,
	osint.adb, osint.ads, osint-b.adb, osint-c.adb,
	par.adb, par-ch10.adb, par-ch11.adb, par-ch2.adb,
	par-ch3.adb, par-ch4.adb, par-ch5.adb, par-ch6.adb,
	par-ch9.adb, par-endh.adb, par-labl.adb, par-load.adb,
	par-prag.adb, par-sync.adb, par-tchk.adb, par-util.adb,
	prj.adb, prj.ads, prj-attr.adb, prj-attr.ads,
	prj-com.adb, prj-com.ads, prj-dect.adb, prj-dect.ads,
	prj-env.adb, prj-env.ads, prj-ext.adb, prj-ext.ads,
	prj-makr.adb, prj-makr.ads, prj-nmsc.adb, prj-nmsc.ads,
	prj-pars.adb, prj-pars.ads, prj-part.adb, prj-part.ads,
	prj-pp.adb, prj-pp.ads, prj-proc.adb, prj-proc.ads,
	prj-strt.adb, prj-strt.ads, prj-tree.adb, prj-tree.ads,
	prj-util.adb, prj-util.ads, raise.c, raise.h,
	repinfo.adb, repinfo.h, restrict.adb, restrict.ads,
	rident.ads, rtsfind.adb, rtsfind.ads, s-addima.ads,
	s-arit64.adb, s-assert.adb, s-assert.ads, s-atacco.adb,
	s-atacco.ads, s-auxdec.adb, s-auxdec.ads, s-bitops.adb,
	scans.ads, scn.adb, scn.ads, s-crc32.adb,
	s-crc32.ads, s-direio.adb, sem.adb, sem.ads,
	sem_aggr.adb, sem_attr.adb, sem_attr.ads, sem_case.adb,
	sem_case.ads, sem_cat.adb, sem_cat.ads, sem_ch10.adb,
	sem_ch11.adb, sem_ch12.adb, sem_ch12.ads, sem_ch13.adb,
	sem_ch13.ads, sem_ch3.adb, sem_ch3.ads, sem_ch4.adb,
	sem_ch5.adb, sem_ch5.ads, sem_ch6.adb, sem_ch6.ads,
	sem_ch7.adb, sem_ch7.ads, sem_ch8.adb, sem_ch8.ads,
	sem_ch9.adb, sem_disp.adb, sem_disp.ads, sem_dist.adb,
	sem_elab.adb, sem_eval.adb, sem_eval.ads, sem_intr.adb,
	sem_maps.adb, sem_mech.adb, sem_prag.adb, sem_prag.ads,
	sem_res.adb, sem_res.ads, sem_type.adb, sem_type.ads,
	sem_util.adb, sem_util.ads, sem_warn.adb, s-errrep.adb,
	s-errrep.ads, s-exctab.adb, s-exctab.ads, s-exnint.ads,
	s-exnllf.ads, s-exnlli.ads, s-expint.ads, s-explli.ads,
	s-expuns.ads, s-fatflt.ads, s-fatgen.adb, s-fatgen.ads,
	s-fatlfl.ads, s-fatllf.ads, s-fatsfl.ads, s-fileio.adb,
	s-fileio.ads, s-finimp.adb, s-finimp.ads, s-finroo.adb,
	s-finroo.ads, sfn_scan.adb, s-gloloc.adb, s-gloloc.ads,
	s-imgdec.adb, s-imgenu.adb, s-imgrea.adb, s-imgwch.adb,
	sinfo.adb, sinfo.ads, s-inmaop.ads, sinput.adb,
	sinput.ads, sinput-d.adb, sinput-l.adb, sinput-l.ads,
	sinput-p.adb, sinput-p.ads, s-interr.adb, s-interr.ads,
	s-intman.ads, s-maccod.ads, s-mastop.adb, s-mastop.ads,
	s-memory.adb, s-memory.ads, snames.adb, snames.ads,
	snames.h, s-osprim.ads, s-parame.ads, s-parint.ads,
	s-pooloc.adb, s-pooloc.ads, s-poosiz.adb, sprint.adb,
	s-proinf.ads, s-scaval.ads, s-secsta.adb, s-secsta.ads,
	s-sequio.adb, s-shasto.adb, s-shasto.ads, s-soflin.ads,
	s-stache.adb, s-stache.ads, s-stalib.adb, s-stalib.ads,
	s-stoele.ads, s-stopoo.ads, s-stratt.adb, s-stratt.ads,
	s-strops.adb, s-strops.ads, s-taasde.adb, s-taasde.ads,
	s-tadeca.adb, s-tadeca.ads, s-tadert.adb, s-tadert.ads,
	s-taenca.adb, s-taenca.ads, s-taprob.adb, s-taprob.ads,
	s-taprop.ads, s-tarest.adb, s-tarest.ads, s-tasdeb.adb,
	s-tasdeb.ads, s-tasinf.adb, s-tasinf.ads, s-tasini.adb,
	s-tasini.ads, s-taskin.adb, s-taskin.ads, s-tasque.adb,
	s-tasque.ads, s-tasren.adb, s-tasren.ads, s-tasres.ads,
	s-tassta.adb, s-tassta.ads, s-tasuti.adb, s-tasuti.ads,
	s-tataat.adb, s-tataat.ads, s-tpinop.adb, s-tpinop.ads,
	s-tpoben.adb, s-tpoben.ads, s-tpobop.adb, s-tpobop.ads,
	s-tposen.adb, s-tposen.ads, s-traceb.adb, s-traceb.ads,
	stringt.adb, stringt.ads, stringt.h, style.ads,
	stylesw.adb, stylesw.ads, s-unstyp.ads, s-vaflop.ads,
	s-valrea.adb, s-valuti.adb, s-vercon.adb, s-vmexta.adb,
	s-wchcnv.ads, s-wchcon.ads, s-widcha.adb, switch.adb,
	switch.ads, switch-b.adb, switch-c.adb, switch-m.adb,
	s-wwdcha.adb, s-wwdwch.adb, sysdep.c, system.ads,
	table.adb, table.ads, targparm.adb, targparm.ads,
	targtyps.c, tbuild.adb, tbuild.ads, tracebak.c,
	trans.c, tree_io.adb, treepr.adb, treeprs.adt,
	ttypes.ads, types.ads, types.h, uintp.adb,
	uintp.ads, uintp.h, uname.adb, urealp.adb,
	urealp.ads, urealp.h, usage.adb, utils2.c,
	utils.c, validsw.adb, validsw.ads, widechar.adb,
	xeinfo.adb, xnmake.adb, xref_lib.adb, xref_lib.ads,
	xr_tabls.adb, xr_tabls.ads, xtreeprs.adb, xsnames.adb,
	einfo.h, sinfo.h, treeprs.ads, nmake.ads, nmake.adb,
	gnatvsn.ads: Merge with ACT tree.

	* gnatvsn.adb: Rewritten in a simpler and more efficient way.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@72751 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 134 insertions, 98 deletions

diff --git a/gcc/ada/eval_fat.adb b/gcc/ada/eval_fat.adb
index fbda4a6611c..f8d14bfe2fa 100644
--- a/gcc/ada/eval_fat.adb
+++ b/gcc/ada/eval_fat.adb
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 1992-2002 Free Software Foundation, Inc.          --
+--          Copyright (C) 1992-2003 Free Software Foundation, Inc.          --
 --                                                                          --
 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
 -- terms of the  GNU General Public License as published  by the Free Soft- --
@@ -25,6 +25,7 @@
 ------------------------------------------------------------------------------
 
 with Einfo;    use Einfo;
+with Errout;   use Errout;
 with Sem_Util; use Sem_Util;
 with Ttypef;   use Ttypef;
 with Targparm; use Targparm;
@@ -72,10 +73,6 @@ package body Eval_Fat is
    --  using biased rounding (halfway cases round away from zero), round to
    --  even, a floor operation or a ceiling operation depending on the setting
    --  of Mode (see corresponding descriptions in Urealp).
-   --
-   --  In case rounding was specified, Rounding_Was_Biased is set True
-   --  if the input was indeed halfway between to machine numbers and
-   --  got rounded away from zero to an odd number.
 
    function Eps_Model (RT : R) return T;
    --  Return the smallest model number of R.
@@ -83,8 +80,11 @@ package body Eval_Fat is
    function Eps_Denorm (RT : R) return T;
    --  Return the smallest denormal of type R.
 
+   function Machine_Emin (RT : R) return Int;
+   --  Return value of the Machine_Emin attribute
+
    function Machine_Mantissa (RT : R) return Nat;
-   --  Get value of machine mantissa
+   --  Return value of the Machine_Mantissa attribute
 
    --------------
    -- Adjacent --
@@ -396,8 +396,6 @@ package body Eval_Fat is
          --  Determine correct rounding based on the remainder
          --  which is in N and the divisor D.
 
-         Rounding_Was_Biased := False; -- Until proven otherwise
-
          case Mode is
             when Round_Even =>
 
@@ -420,10 +418,6 @@ package body Eval_Fat is
 
                if N * 2 >= D then
                   Fraction := Fraction + 1;
-
-                  Rounding_Was_Biased := Even and then N * 2 = D;
-                  --  Check for the case where the result is actually
-                  --  different from Round_Even.
                end if;
 
             when Ceiling =>
@@ -451,54 +445,9 @@ package body Eval_Fat is
    ----------------
 
    function Eps_Denorm (RT : R) return T is
-      Digs : constant UI := Digits_Value (RT);
-      Emin : Int;
-      Mant : Int;
-
    begin
-      if Vax_Float (RT) then
-         if Digs = VAXFF_Digits then
-            Emin := VAXFF_Machine_Emin;
-            Mant := VAXFF_Machine_Mantissa;
-
-         elsif Digs = VAXDF_Digits then
-            Emin := VAXDF_Machine_Emin;
-            Mant := VAXDF_Machine_Mantissa;
-
-         else
-            pragma Assert (Digs = VAXGF_Digits);
-            Emin := VAXGF_Machine_Emin;
-            Mant := VAXGF_Machine_Mantissa;
-         end if;
-
-      elsif Is_AAMP_Float (RT) then
-         if Digs = AAMPS_Digits then
-            Emin := AAMPS_Machine_Emin;
-            Mant := AAMPS_Machine_Mantissa;
-
-         else
-            pragma Assert (Digs = AAMPL_Digits);
-            Emin := AAMPL_Machine_Emin;
-            Mant := AAMPL_Machine_Mantissa;
-         end if;
-
-      else
-         if Digs = IEEES_Digits then
-            Emin := IEEES_Machine_Emin;
-            Mant := IEEES_Machine_Mantissa;
-
-         elsif Digs = IEEEL_Digits then
-            Emin := IEEEL_Machine_Emin;
-            Mant := IEEEL_Machine_Mantissa;
-
-         else
-            pragma Assert (Digs = IEEEX_Digits);
-            Emin := IEEEX_Machine_Emin;
-            Mant := IEEEX_Machine_Mantissa;
-         end if;
-      end if;
-
-      return Float_Radix ** UI_From_Int (Emin - Mant);
+      return Float_Radix ** UI_From_Int
+                                  (Machine_Emin (RT) - Machine_Mantissa (RT));
    end Eps_Denorm;
 
    ---------------
@@ -506,45 +455,8 @@ package body Eval_Fat is
    ---------------
 
    function Eps_Model (RT : R) return T is
-      Digs : constant UI := Digits_Value (RT);
-      Emin : Int;
-
    begin
-      if Vax_Float (RT) then
-         if Digs = VAXFF_Digits then
-            Emin := VAXFF_Machine_Emin;
-
-         elsif Digs = VAXDF_Digits then
-            Emin := VAXDF_Machine_Emin;
-
-         else
-            pragma Assert (Digs = VAXGF_Digits);
-            Emin := VAXGF_Machine_Emin;
-         end if;
-
-      elsif Is_AAMP_Float (RT) then
-         if Digs = AAMPS_Digits then
-            Emin := AAMPS_Machine_Emin;
-
-         else
-            pragma Assert (Digs = AAMPL_Digits);
-            Emin := AAMPL_Machine_Emin;
-         end if;
-
-      else
-         if Digs = IEEES_Digits then
-            Emin := IEEES_Machine_Emin;
-
-         elsif Digs = IEEEL_Digits then
-            Emin := IEEEL_Machine_Emin;
-
-         else
-            pragma Assert (Digs = IEEEX_Digits);
-            Emin := IEEEX_Machine_Emin;
-         end if;
-      end if;
-
-      return Float_Radix ** UI_From_Int (Emin);
+      return Float_Radix ** UI_From_Int (Machine_Emin (RT));
    end Eps_Model;
 
    --------------
@@ -624,19 +536,143 @@ package body Eval_Fat is
    -- Machine --
    -------------
 
-   function Machine (RT : R; X : T; Mode : Rounding_Mode) return T is
+   function Machine
+     (RT    : R;
+      X     : T;
+      Mode  : Rounding_Mode;
+      Enode : Node_Id)
+      return  T
+   is
+      pragma Warnings (Off, Enode); -- not yet referenced
+
       X_Frac : T;
       X_Exp  : UI;
+      Emin   : constant UI := UI_From_Int (Machine_Emin (RT));
 
    begin
       if UR_Is_Zero (X) then
          return X;
+
       else
          Decompose (RT, X, X_Frac, X_Exp, Mode);
+
+         --  Case of denormalized number or (gradual) underflow
+
+         --  A denormalized number is one with the minimum exponent Emin, but
+         --  that breaks the assumption that the first digit of the mantissa
+         --  is a one. This allows the first non-zero digit to be in any
+         --  of the remaining Mant - 1 spots. The gap between subsequent
+         --  denormalized numbers is the same as for the smallest normalized
+         --  numbers. However, the number of significant digits left decreases
+         --  as a result of the mantissa now having leading seros.
+
+         if X_Exp < Emin then
+            declare
+               Emin_Den : constant UI :=
+                            UI_From_Int
+                              (Machine_Emin (RT) - Machine_Mantissa (RT) + 1);
+            begin
+               if X_Exp < Emin_Den or not Denorm_On_Target then
+                  if UR_Is_Negative (X) then
+                     Error_Msg_N
+                       ("floating-point value underflows to -0.0?", Enode);
+                     return Ureal_M_0;
+
+                  else
+                     Error_Msg_N
+                       ("floating-point value underflows to 0.0?", Enode);
+                     return Ureal_0;
+                  end if;
+
+               elsif Denorm_On_Target then
+
+                  --  Emin - Mant <= X_Exp < Emin, so result is denormal.
+                  --  Handle gradual underflow by first computing the
+                  --  number of significant bits still available for the
+                  --  mantissa and then truncating the fraction to this
+                  --  number of bits.
+
+                  --  If this value is different from the original
+                  --  fraction, precision is lost due to gradual underflow.
+
+                  --  We probably should round here and prevent double
+                  --  rounding as a result of first rounding to a model
+                  --  number and then to a machine number. However, this
+                  --  is an extremely rare case that is not worth the extra
+                  --  complexity. In any case, a warning is issued in cases
+                  --  where gradual underflow occurs.
+
+                  declare
+                     Denorm_Sig_Bits : constant UI := X_Exp - Emin_Den + 1;
+
+                     X_Frac_Denorm   : constant T := UR_From_Components
+                       (UR_Trunc (Scaling (RT, abs X_Frac, Denorm_Sig_Bits)),
+                        Denorm_Sig_Bits,
+                        Radix,
+                        UR_Is_Negative (X));
+
+                  begin
+                     if X_Frac_Denorm /= X_Frac then
+                        Error_Msg_N
+                          ("gradual underflow causes loss of precision?",
+                           Enode);
+                        X_Frac := X_Frac_Denorm;
+                     end if;
+                  end;
+               end if;
+            end;
+         end if;
+
          return Scaling (RT, X_Frac, X_Exp);
       end if;
    end Machine;
 
+   ------------------
+   -- Machine_Emin --
+   ------------------
+
+   function Machine_Emin (RT : R) return Int is
+      Digs : constant UI := Digits_Value (RT);
+      Emin : Int;
+
+   begin
+      if Vax_Float (RT) then
+         if Digs = VAXFF_Digits then
+            Emin := VAXFF_Machine_Emin;
+
+         elsif Digs = VAXDF_Digits then
+            Emin := VAXDF_Machine_Emin;
+
+         else
+            pragma Assert (Digs = VAXGF_Digits);
+            Emin := VAXGF_Machine_Emin;
+         end if;
+
+      elsif Is_AAMP_Float (RT) then
+         if Digs = AAMPS_Digits then
+            Emin := AAMPS_Machine_Emin;
+
+         else
+            pragma Assert (Digs = AAMPL_Digits);
+            Emin := AAMPL_Machine_Emin;
+         end if;
+
+      else
+         if Digs = IEEES_Digits then
+            Emin := IEEES_Machine_Emin;
+
+         elsif Digs = IEEEL_Digits then
+            Emin := IEEEL_Machine_Emin;
+
+         else
+            pragma Assert (Digs = IEEEX_Digits);
+            Emin := IEEEX_Machine_Emin;
+         end if;
+      end if;
+
+      return Emin;
+   end Machine_Emin;
+
    ----------------------
    -- Machine_Mantissa --
    ----------------------