Test suite crashes on PPC64

[Zack Weinberg]

On powerpc64-unknown-linux-gnu, with unmodified master glibc and GCC
7, I'm seeing the test suite fall over while trying to build locales:

Generating locale de_DE.ISO-8859-1: this might take a while...
Inconsistency detected by ld.so: get-dynamic-info.h: 146:
elf_get_dynamic_info: Assertion `info[DT_RUNPATH] == NULL' failed!
Charmap: "ISO-8859-1" Inputfile: "de_DE" Outputdir: "de_DE.ISO-8859-1" failed
/bin/sh: line 3:
/home/zackw/glibc/build-normal/localedata/de_DE.ISO-8859-1/LC_CTYPE.test-result:
No such file or directory
make[2]: *** [/home/zackw/glibc/build-normal/localedata/de_DE.ISO-8859-1/LC_CTYPE]
Error 1

Anyone have any idea what might be wrong?  This makes it hard to debug
my scanf patches...

zw