printf float on arm

Thu Mar 1 13:53:51 UTC 2007

Hi all,

I build a firmware (rootfs+kernel) for my target ARM PXA255 using
buildroot.

On this target, the printf of float number is broken. I mean

printf("%12.3f\n", 123.456);

Doesn't print :      123.456
but           :       123456

I searched the web and the list about this issue and haven't find a
good response. I know that some time ago, the problem was present in
the uClibc and I think it is now fixed. But maybe not for ARM arch.
Or my configuration maybe lack the right options settings.

Is the problem fixed for ARM or is it always present ?

My target is built with :

uClibc-0.9.28
uClibc-locale-030818
busybox-1.2.1
gcc-4.0.3
libfloat_990616-3.diff
libfloat_990616
(linux-2.6.17.13 && linux-headers-2.6.17.13-09092006) || linux-2.6.19
xenomai-2.3.0

And my uClibc configuration is at the end.

Thanks for any tips,
Philippe

#
# Automatically generated make config: don't edit
#
# TARGET_alpha is not set
TARGET_arm=y
# TARGET_bfin is not set
# TARGET_cris is not set
# TARGET_e1 is not set
# TARGET_frv is not set
# TARGET_h8300 is not set
# TARGET_i386 is not set
# TARGET_i960 is not set
# TARGET_m68k is not set
# TARGET_microblaze is not set
# TARGET_mips is not set
# TARGET_nios is not set
# TARGET_nios2 is not set
# TARGET_powerpc is not set
# TARGET_sh is not set
# TARGET_sh64 is not set
# TARGET_sparc is not set
# TARGET_v850 is not set
# TARGET_x86_64 is not set

#
# Target Architecture Features and Options
#
HAVE_ELF=y
ARCH_SUPPORTS_LITTLE_ENDIAN=y
TARGET_ARCH="arm"
ARCH_SUPPORTS_BIG_ENDIAN=y
# CONFIG_GENERIC_ARM is not set
# CONFIG_ARM610 is not set
# CONFIG_ARM710 is not set
# CONFIG_ARM720T is not set
# CONFIG_ARM920T is not set
# CONFIG_ARM922T is not set
# CONFIG_ARM926T is not set
# CONFIG_ARM1136JF_S is not set
# CONFIG_ARM_SA110 is not set
# CONFIG_ARM_SA1100 is not set
CONFIG_ARM_XSCALE=y
ARCH_LITTLE_ENDIAN=y
# ARCH_BIG_ENDIAN is not set
# ARCH_HAS_NO_MMU is not set
ARCH_HAS_MMU=y
UCLIBC_HAS_FLOATS=y
# HAS_FPU is not set
UCLIBC_HAS_SOFT_FLOAT=y
DO_C99_MATH=y
KERNEL_SOURCE=""
C_SYMBOL_PREFIX=""
HAVE_DOT_CONFIG=y

#
# General Library Settings
#
# HAVE_NO_PIC is not set
DOPIC=y
# HAVE_NO_SHARED is not set
HAVE_SHARED=y
# ARCH_HAS_NO_LDSO is not set
BUILD_UCLIBC_LDSO=y
FORCE_SHAREABLE_TEXT_SEGMENTS=y
LDSO_LDD_SUPPORT=y
LDSO_CACHE_SUPPORT=y
# LDSO_PRELOAD_FILE_SUPPORT is not set
LDSO_BASE_FILENAME="ld.so"
# LDSO_RUNPATH is not set
# DL_FINI_CRT_COMPAT is not set
UCLIBC_CTOR_DTOR=y
# HAS_NO_THREADS is not set
UCLIBC_HAS_THREADS=y
PTHREADS_DEBUG_SUPPORT=y
UCLIBC_HAS_LFS=y
# UCLIBC_STATIC_LDCONFIG is not set
MALLOC=y
# MALLOC_SIMPLE is not set
# MALLOC_STANDARD is not set
MALLOC_GLIBC_COMPAT=y
UCLIBC_DYNAMIC_ATEXIT=y
HAS_SHADOW=y
UNIX98PTY_ONLY=y
ASSUME_DEVPTS=y
UCLIBC_HAS_TM_EXTENSIONS=y
UCLIBC_HAS_TZ_CACHING=y
UCLIBC_HAS_TZ_FILE=y
UCLIBC_HAS_TZ_FILE_READ_MANY=y
UCLIBC_TZ_FILE_PATH="/etc/TZ"

#
# Networking Support
#
# UCLIBC_HAS_IPV6 is not set
UCLIBC_HAS_RPC=y
# UCLIBC_HAS_FULL_RPC is not set

#
# String and Stdio Support
#
UCLIBC_HAS_STRING_GENERIC_OPT=y
UCLIBC_HAS_STRING_ARCH_OPT=y
UCLIBC_HAS_CTYPE_TABLES=y
UCLIBC_HAS_CTYPE_SIGNED=y
# UCLIBC_HAS_CTYPE_UNSAFE is not set
UCLIBC_HAS_CTYPE_CHECKED=y
# UCLIBC_HAS_CTYPE_ENFORCED is not set
UCLIBC_HAS_WCHAR=y
UCLIBC_HAS_LOCALE=y
UCLIBC_PREGENERATED_LOCALE_DATA=y
UCLIBC_DOWNLOAD_PREGENERATED_LOCALE_DATA=y
UCLIBC_HAS_XLOCALE=y
UCLIBC_HAS_HEXADECIMAL_FLOATS=y
UCLIBC_HAS_GLIBC_DIGIT_GROUPING=y
UCLIBC_HAS_SCANF_LENIENT_DIGIT_GROUPING=y
UCLIBC_HAS_GLIBC_CUSTOM_PRINTF=y
UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS=9
# UCLIBC_HAS_SCANF_GLIBC_A_FLAG is not set
# UCLIBC_HAS_STDIO_BUFSIZ_NONE is not set
# UCLIBC_HAS_STDIO_BUFSIZ_256 is not set
# UCLIBC_HAS_STDIO_BUFSIZ_512 is not set
# UCLIBC_HAS_STDIO_BUFSIZ_1024 is not set
# UCLIBC_HAS_STDIO_BUFSIZ_2048 is not set
UCLIBC_HAS_STDIO_BUFSIZ_4096=y
# UCLIBC_HAS_STDIO_BUFSIZ_8192 is not set
UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE=y
# UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4 is not set
# UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8 is not set
# UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT is not set
UCLIBC_HAS_STDIO_GETC_MACRO=y
UCLIBC_HAS_STDIO_PUTC_MACRO=y
UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION=y
# UCLIBC_HAS_FOPEN_LARGEFILE_MODE is not set
UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE=y
UCLIBC_HAS_GLIBC_CUSTOM_STREAMS=y
UCLIBC_HAS_PRINTF_M_SPEC=y
UCLIBC_HAS_ERRNO_MESSAGES=y
# UCLIBC_HAS_SYS_ERRLIST is not set
UCLIBC_HAS_SIGNUM_MESSAGES=y
# UCLIBC_HAS_SYS_SIGLIST is not set
UCLIBC_HAS_GNU_GETOPT=y

#
# Big and Tall
#
UCLIBC_HAS_REGEX=y
# UCLIBC_HAS_WORDEXP is not set
# UCLIBC_HAS_FTW is not set
UCLIBC_HAS_GLOB=y

#
# Library Installation Options
#
SHARED_LIB_LOADER_PREFIX="/lib"
RUNTIME_PREFIX="/"
DEVEL_PREFIX="/usr/"

#
# uClibc security related options
#
# UCLIBC_SECURITY is not set

#
# uClibc development/debugging options
#
CROSS_COMPILER_PREFIX=""
# DODEBUG is not set
# DODEBUG_PT is not set
# DOASSERTS is not set
# SUPPORT_LD_DEBUG is not set
# SUPPORT_LD_DEBUG_EARLY is not set
# UCLIBC_MALLOC_DEBUGGING is not set
WARNINGS="-Wall"
# UCLIBC_MJN3_ONLY is not set