Managed a bootstrap that didn't blow up.
At the moment the assembly output from a trivial test shows that the IBM
extended precision long double type is the default unless one actually
asks for the IEEE754-2008 128-bit datatype.
dclarke@nix:~/pgm/C/ieee754$
PATH=/usr/local/build/gcc-7.3.0_linux_4.15.0-2-powerpc64_ppc64.005/gcc:$PATH
xgcc
-I/usr/local/build/gcc-7.3.0_linux_4.15.0-2-powerpc64_ppc64.005/gcc/include
-m64 -g -Wl,-rpath=/usr/local/lib -mcpu=970 -maltivec -mfull-toc
-mregnames -mabi=ieeelongdouble -S -o ld.s ld.c
xgcc: warning: using IEEE extended precision long double
cc1: warning: using IEEE extended precision long double
dclarke@nix:~/pgm/C/ieee754$ grep "quad" ld.s | grep "0x"
.quad 0x4000921fb54442d1,0x8469898cc51701b8
That data is correct.
dclarke@nix:~/pgm/C/ieee754$
PATH=/usr/local/build/gcc-7.3.0_linux_4.15.0-2-powerpc64_ppc64.005/gcc:$PATH
xgcc
-I/usr/local/build/gcc-7.3.0_linux_4.15.0-2-powerpc64_ppc64.005/gcc/include
-m64 -g -Wl,-rpath=/usr/local/lib -mcpu=970 -maltivec -mfull-toc
-mregnames -mabi=ibmlongdouble -S -o ld.s ld.c
xgcc: warning: using IBM extended precision long double
cc1: warning: using IBM extended precision long double
dclarke@nix:~/pgm/C/ieee754$ grep "quad" ld.s | grep "0x"
.quad 0x400921fb54442d18,0x3ca1a62633145c06
That is a whole other beast of a different colour.
dclarke@nix:~/pgm/C/ieee754$
PATH=/usr/local/build/gcc-7.3.0_linux_4.15.0-2-powerpc64_ppc64.005/gcc:$PATH
xgcc
-I/usr/local/build/gcc-7.3.0_linux_4.15.0-2-powerpc64_ppc64.005/gcc/include
-m64 -g -Wl,-rpath=/usr/local/lib -mcpu=970 -maltivec -mfull-toc
-mregnames -S -o ld.s ld.c
dclarke@nix:~/pgm/C/ieee754$ grep "quad" ld.s | grep "0x"
.quad 0x400921fb54442d18,0x3ca1a62633145c06
dclarke@nix:~/pgm/C/ieee754$
So the default is the IBM type. No idea on the libquadmath yet.
I should have more info on this issue in another 16 or 20 hours.
Dennis
