glibc/stdio-common/Makefile
Joseph Myers 646c2833ee Fix scanf rounding of negative floating-point numbers (bug 23280).
As reported in bug 23280, scanf functions produce incorrectly rounded
result for floating-point formats in FE_UPWARD and FE_DOWNWARD modes,
because they pass the input with sign removed to strtod functions, and
then negate the result if there was a '-' at the start of the input.

This patch fixes this by arranging for the sign to be passed to strtod
rather than scanf doing the negation itself.  In turn, keeping the
sign around in the buffer being built up for strtod requires updating
places that examine char_buffer_size (&charbuf) to allow for the sign
being there as an extra character.

Tested for x86_64.

	[BZ #23280]
	* stdio-common/vfscanf.c (_IO_vfscanf_internal): Pass sign of
	floating-point number to strtod functions rather than possibly
	negating result of those functions.
	* stdio-common/tst-scanf-round.c: New file.
	* stdio-common/Makefile (tests): Add tst-scanf-round.
	($(objpfx)tst-scanf-round): Depend on $(libm).
2018-06-19 11:52:18 +00:00

163 lines
5.9 KiB
Makefile

# Copyright (C) 1991-2018 Free Software Foundation, Inc.
# This file is part of the GNU C Library.
# The GNU C Library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
# The GNU C Library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
# You should have received a copy of the GNU Lesser General Public
# License along with the GNU C Library; if not, see
# <http://www.gnu.org/licenses/>.
#
# Specific makefile for stdio-common.
#
subdir := stdio-common
include ../Makeconfig
headers := stdio_ext.h printf.h bits/printf-ldbl.h bits/stdio_lim.h
routines := \
ctermid cuserid \
_itoa _itowa itoa-digits itoa-udigits itowa-digits \
vfprintf vprintf printf_fp reg-printf printf-prs printf_fphex \
reg-modifier reg-type \
printf_size fprintf printf snprintf sprintf asprintf dprintf \
vfwprintf vfscanf vfwscanf \
fscanf scanf sscanf \
perror psignal \
tmpfile tmpfile64 tmpnam tmpnam_r tempnam tempname \
getline getw putw \
remove rename renameat \
flockfile ftrylockfile funlockfile \
isoc99_scanf isoc99_vscanf isoc99_fscanf isoc99_vfscanf isoc99_sscanf \
isoc99_vsscanf \
psiginfo gentempfd
aux := errlist siglist printf-parsemb printf-parsewc fxprintf
tests := tstscanf test_rdwr test-popen tstgetln test-fseek \
temptest tst-fileno test-fwrite tst-ungetc tst-ferror \
xbug errnobug \
bug1 bug2 bug3 bug4 bug5 bug6 bug7 bug8 bug9 bug10 bug11 bug12 bug13 \
tfformat tiformat tllformat tstdiomisc tst-printfsz tst-wc-printf \
scanf1 scanf2 scanf3 scanf4 scanf5 scanf7 scanf8 scanf9 scanf10 \
scanf11 scanf12 tst-tmpnam tst-cookie tst-obprintf tst-sscanf \
tst-swprintf tst-fseek tst-fmemopen test-vfprintf tst-gets \
tst-perror tst-sprintf tst-rndseek tst-fdopen tst-fphex bug14 \
tst-popen tst-unlockedio tst-fmemopen2 tst-put-error tst-fgets \
tst-fwrite bug16 bug17 tst-swscanf tst-sprintf2 bug18 bug18a \
bug19 bug19a tst-popen2 scanf13 scanf14 scanf15 bug20 bug21 bug22 \
scanf16 scanf17 tst-setvbuf1 tst-grouping bug23 bug24 \
bug-vfprintf-nargs tst-long-dbl-fphex tst-fphex-wide tst-sprintf3 \
bug25 tst-printf-round bug23-2 bug23-3 bug23-4 bug26 tst-fmemopen3 \
tst-printf-bz18872 tst-vfprintf-width-prec tst-fmemopen4 \
tst-vfprintf-user-type \
tst-vfprintf-mbs-prec \
tst-scanf-round \
test-srcs = tst-unbputc tst-printf
ifeq ($(run-built-tests),yes)
tests-special += $(objpfx)tst-unbputc.out $(objpfx)tst-printf.out \
$(objpfx)tst-printf-bz18872-mem.out \
$(objpfx)tst-setvbuf1-cmp.out \
$(objpfx)tst-vfprintf-width-prec-mem.out
generated += tst-printf-bz18872.c tst-printf-bz18872.mtrace \
tst-printf-bz18872-mem.out \
tst-vfprintf-width-prec.mtrace tst-vfprintf-width-prec-mem.out
endif
include ../Rules
ifeq ($(run-built-tests),yes)
LOCALES := de_DE.ISO-8859-1 de_DE.UTF-8 en_US.ISO-8859-1 ja_JP.EUC-JP
include ../gen-locales.mk
$(objpfx)bug14.out: $(gen-locales)
$(objpfx)scanf13.out: $(gen-locales)
$(objpfx)test-vfprintf.out: $(gen-locales)
$(objpfx)tst-grouping.out: $(gen-locales)
$(objpfx)tst-sprintf.out: $(gen-locales)
$(objpfx)tst-sscanf.out: $(gen-locales)
$(objpfx)tst-swprintf.out: $(gen-locales)
$(objpfx)tst-vfprintf-mbs-prec.out: $(gen-locales)
endif
tst-printf-bz18872-ENV = MALLOC_TRACE=$(objpfx)tst-printf-bz18872.mtrace
tst-vfprintf-width-prec-ENV = \
MALLOC_TRACE=$(objpfx)tst-vfprintf-width-prec.mtrace
$(objpfx)tst-unbputc.out: tst-unbputc.sh $(objpfx)tst-unbputc
$(SHELL) $< $(common-objpfx) '$(test-program-prefix)' > $@; \
$(evaluate-test)
$(objpfx)tst-printf.out: tst-printf.sh $(objpfx)tst-printf
$(SHELL) $< $(common-objpfx) '$(test-program-prefix)' > $@; \
$(evaluate-test)
# We generate this source because it requires a printf invocation with
# 10K arguments.
$(objpfx)tst-printf-bz18872.c: tst-printf-bz18872.sh
rm -f $@ && $(BASH) $^ > $@.new && mv $@.new $@
$(objpfx)tst-%-mem.out: $(objpfx)tst-%.out
$(common-objpfx)malloc/mtrace $(objpfx)tst-$*.mtrace > $@; \
$(evaluate-test)
CFLAGS-vfprintf.c += -Wno-uninitialized
CFLAGS-vfwprintf.c += -Wno-uninitialized
CFLAGS-tmpfile.c += -fexceptions
CFLAGS-tmpfile64.c += -fexceptions
CFLAGS-tempname.c += -fexceptions
CFLAGS-psignal.c += -fexceptions
CFLAGS-vprintf.c += -fexceptions
CFLAGS-cuserid.c += -fexceptions
CFLAGS-vfprintf.c += -fexceptions
CFLAGS-fprintf.c += -fexceptions
CFLAGS-printf.c += -fexceptions
CFLAGS-vfwprintf.c += -fexceptions
CFLAGS-vfscanf.c += -fexceptions
CFLAGS-vfwscanf.c += -fexceptions
CFLAGS-fscanf.c += -fexceptions
CFLAGS-scanf.c += -fexceptions
CFLAGS-isoc99_vfscanf.c += -fexceptions
CFLAGS-isoc99_vscanf.c += -fexceptions
CFLAGS-isoc99_fscanf.c += -fexceptions
CFLAGS-isoc99_scanf.c += -fexceptions
CFLAGS-errlist.c += $(fno-unit-at-a-time)
CFLAGS-siglist.c += $(fno-unit-at-a-time)
# The following is a hack since we must compile scanf1{5,7}.c without any
# GNU extension. The latter are needed, though, when internal headers
# are used. So made sure we see the installed headers first.
CFLAGS-scanf15.c += -I../libio -I../stdlib -I../wcsmbs -I../time -I../string \
-I../wctype
CFLAGS-scanf17.c += -I../libio -I../stdlib -I../wcsmbs -I../time -I../string \
-I../wctype
# tst-gets.c tests a deprecated function.
CFLAGS-tst-gets.c += -Wno-deprecated-declarations
CPPFLAGS += $(libio-mtsafe)
$(objpfx)tst-setvbuf1.out: /dev/null $(objpfx)tst-setvbuf1
$(test-program-cmd) > $@ 2>&1; \
$(evaluate-test)
$(objpfx)tst-setvbuf1-cmp.out: tst-setvbuf1.expect $(objpfx)tst-setvbuf1.out
cmp $^ > $@; \
$(evaluate-test)
$(objpfx)tst-printf-round: $(libm)
$(objpfx)tst-scanf-round: $(libm)