Using gcc-4.6.2-1.fc16.x86_64 on HEAD (commit 3284b799), I get:
make[2]: Entering directory `/home/jistone/src/elfutils/src'
gcc -D_GNU_SOURCE -DHAVE_CONFIG_H
-DLOCALEDIR='"/usr/local/share/locale"' -DDEBUGPRED=0
-DSRCDIR=\"/home/jistone/src/elfutils/src\"
-DOBJDIR=\"/home/jistone/src/elfutils/src\" -I. -I.. -I. -I. -I../lib -I..
-I./../libelf -I./../libebl -I./../libdw -I./../libdwfl -I./../libasm -std=gnu99 -Wall
-Wshadow -Werror -Wunused -Wextra -Wformat=2 -g -O2 -MT arlib-argp.o -MD -MP -MF
.deps/arlib-argp.Tpo -c -o arlib-argp.o arlib-argp.c
arlib-argp.c:100:5: error: missing initializer [-Werror=missing-field-initializers]
arlib-argp.c:100:5: error: (near initialization for ‘arlib_argp_children[1].flags’)
[-Werror=missing-field-initializers]
cc1: all warnings being treated as errors