I'm using the latest snapshot (1.5Z) and a very recent pkgsrc, but when
building perl5, I get:

===> Building for perl-5.6.1nb6
        AutoSplitting perl library
LD_LIBRARY_PATH=/usr/tmp/lang/perl5/work.sparc64/perl-5.6.1 ./miniperl -Ilib -e 'use AutoSplit;  autosplit_lib_modules(@ARGV)' lib/*.pm lib/*/*.pm

        Skipping /usr/tmp/lang/perl5/work.sparc64/perl-5.6.1/lib/auto/DynaLoader/DynaLoader.a (directory does not exist)
LD_LIBRARY_PATH=/usr/tmp/lang/perl5/work.sparc64/perl-5.6.1 cc -o perl -Wl,-R/usr/pkg/lib  -L/usr/pkg/lib -Wl,-whole-archive -lgcc -Wl,-no-whole-archive                        -Wl,-E -Wl,-R/lib  -Wl,-R/usr/pkg/lib/perl5/5.6.1/sparc64-netbsd/CORE perlmain.o lib/auto/DynaLoader/DynaLoader.a  -L. -lperl `cat ext.libs` -lm -lcrypt
/usr/lib/libgcc.a(_fixtfdi.o): In function `__fixtfdi':
_fixtfdi.o(.text+0x18): undefined reference to `_Qp_flt'
/usr/lib/libgcc.a(_fixunstfdi.o): In function `__fixunstfdi':
_fixunstfdi.o(.text+0x18): undefined reference to `_Qp_flt'
_fixunstfdi.o(.text+0x3c): undefined reference to `_Qp_mul'
_fixunstfdi.o(.text+0x44): undefined reference to `_Qp_qtoui'
_fixunstfdi.o(.text+0x70): undefined reference to `_Qp_add'
_fixunstfdi.o(.text+0x84): undefined reference to `_Qp_sub'
_fixunstfdi.o(.text+0xa0): undefined reference to `_Qp_flt'
_fixunstfdi.o(.text+0xb4): undefined reference to `_Qp_qtoui'
_fixunstfdi.o(.text+0xc8): undefined reference to `_Qp_qtoui'
/usr/lib/libgcc.a(_floatditf.o): In function `__floatditf':
_floatditf.o(.text+0x4): undefined reference to `_Qp_itoq'
_floatditf.o(.text+0x1c): undefined reference to `_Qp_mul'
_floatditf.o(.text+0x28): undefined reference to `_Qp_mul'
_floatditf.o(.text+0x38): undefined reference to `_Qp_itoq'
_floatditf.o(.text+0x5c): undefined reference to `_Qp_add'
_floatditf.o(.text+0x70): undefined reference to `_Qp_add'
*** Error code 1

Stop.
p_qtoui'
_fixunstfdi.o(.text+0x70): undefined reference to `_Qp_add'
_fixunstfdi.o(.text+0x84): undefined reference to `_Qp_sub'
_fixunstfdi.o(.text+0xa0): undefined reference to `_Qp_flt'
_fixunstfdi.o(.text+0xb4): undefined reference to `_Qp_qtoui'
_fixunstfdi.o(.text+0xc8): undefined reference to `_Qp_qtoui'
/usr/lib/libgcc.a(_floatditf.o): In function `__floatditf':
_floatditf.o(.text+0x4): undefined reference to `_Qp_itoq'
_floatditf.o(.text+0x1c): undefined reference to `_Qp_mul'
_floatditf.o(.text+0x28): undefined reference to `_Qp_mul'
_floatditf.o(.text+0x38): undefined reference to `_Qp_itoq'
_floatditf.o(.text+0x5c): undefined reference to `_Qp_add'
_floatditf.o(.text+0x70): undefined reference to `_Qp_add'
*** Error code 1

Stop.

Looks like a libgcc bug rather than a perl problem, per se.

-- 
Stephen