Fatal error: Junk at end of expression "rdi)"

Running on x86_64 NetBSD 10.0_BETA, gcc (nb1 20220722) 10.4.0

Tying to build the VAX cross compiler, using:

` ./build-vax-netbsd.sh 10.4.0`

Any idea why this failure happens?

```
/bin/sh /home/bill/build-netbsd/NetBSD-src/tools/gcc/../../external/gpl3/gcc.old/dist/gcc/mkconfig.sh bconfig.h
c++ -c -O -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wno-error=format-diag -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -DHAVE_CONFIG_H -DGENERATOR_FILE -I. -Ibuild -I/home/bill/build-netbsd/NetBSD-src/tools/gcc/../../external/gpl3/gcc.old/dist/gcc -I/home/bill/build-netbsd/NetBSD-src/tools/gcc/../../external/gpl3/gcc.old/dist/gcc/build -I/home/bill/build-netbsd/NetBSD-src/tools/gcc/../../external/gpl3/gcc.old/dist/gcc/../include -I/home/bill/build-netbsd/NetBSD-src/tools/gcc/../../external/gpl3/gcc.old/dist/gcc/../libcpp/include -DNETBSD_TOOLS -DTARGET_SYSTEM_ROOT=0 -DTARGET_SYSTEM_ROOT_RELOCATABLE \
-o build/genmodes.o /home/bill/build-netbsd/NetBSD-src/tools/gcc/../../external/gpl3/gcc.old/dist/gcc/genmodes.c
/tmp//ccEY1yqa.s: Assembler messages:
/tmp//ccEY1yqa.s:7: Error: bad expression
/tmp//ccEY1yqa.s:7: Error: found 'r', expected: ')'
/tmp//ccEY1yqa.s:7: Fatal error: Junk at end of expression "rdi)"
nbgmake[1]: *** [build/genmodes.o] Error 1
nbgmake[1]: Leaving directory `/home/bill/build-netbsd/NetBSD-src/tools/gcc/obj/build/gcc'
nbgmake: *** [all-gcc] Error 2
```

Bill

Start by reproducing ./build-vax-netbsd.sh 10.4.0 and inspect the generated assembly for genmodes.c, especially line 7 of /tmp//ccEY1yqa.s. Determine why the assembler rejects the expression ending in "rdi)" and confirm the build completes after the cause is addressed.

Written by the indexing model from the issue text.