Hi Janneke,

On Mon, 09 Jul 2018 18:57:16 +0200
Jan Nieuwenhuizen <janneke@gnu.org> wrote:

>      i386-unknown-linux-gcc --sysroot=/gnu/store/jdjpfzjr2zf3xbf7ssl11ljwpq7spid8-glibc-mesboot-2.3.6/include   -g -O2 -O2  -g -O2 -DIN_GCC   -W -Wall -Wwrite-strings -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include   -fpic -g -DIN_LIBGCC2 -fno-stack-protector   -fpic -I. -I. -I../../host-i386-unknown-linux/gcc -I../.././libgcc -I../.././libgcc/. -I../.././libgcc/../gcc -I../.././libgcc/../include  -DHAVE_CC_TLS  -DUSE_TLS -o _muldi3.o -MT _muldi3.o -MD -MP -MF _muldi3.dep -DL_muldi3 -c ../.././libgcc/libgcc2.c 
>      In file included from ../.././libgcc/libgcc2.c:58:
>      ../.././libgcc/libgcc2.h:157: error: unable to emulate 'TF'
>      ../.././libgcc/libgcc2.h:158: error: unable to emulate 'TC'
>      ../.././libgcc/libgcc2.h:161: error: unknown machine mode 'libgcc_cmp_return'
>      ../.././libgcc/libgcc2.h:162: error: unknown machine mode 'libgcc_shift_count'
>      ../.././libgcc/libgcc2.h:372: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__muldi3'
>      ../.././libgcc/libgcc2.h:373: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__divdi3'
>      ../.././libgcc/libgcc2.h:374: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__udivdi3'
>      ../.././libgcc/libgcc2.h:375: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__umoddi3'
>      ../.././libgcc/libgcc2.h:376: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__moddi3'
>      ...
> 
> Gcc-4.7.4 advertises it can be built with gcc-2.95 and binutils-2.13.1
> and glibc-2.2.5.

https://gcc.gnu.org/onlinedocs/gccint/Machine-Modes.html

TFmode is for 128 bit floats.

https://gcc.gnu.org/ml/gcc-patches/2008-06/msg01747.html
https://gcc.gnu.org/onlinedocs/gcc-4.8.5/gccint/Type-Layout.html

The softfp emulation is in libgcc.