Comment 1 for bug 714921

Nonreduced preprocessed source attached. Build with this command (natively on arm) to reproduce:

/usr/lib/gcc/arm-linux-gnueabi/4.5.2/cc1 -quiet gcc-oom.i -quiet -dumpbase translate.c -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16 -mthumb -auxbase-strip translate.o -g -O2 -Werror -Wstrict-prototypes -Wredundant-decls -Wall -Wundef -Wendif-labels -Wwrite-strings -Wmissing-prototypes -Wmissing-include-dirs -Wempty-body -Wnested-externs -Wformat-security -Wformat-y2k -Winit-self -Wignored-qualifiers -Wold-style-declaration -Wold-style-definition -Wtype-limits -fno-strict-aliasing -fstack-protector -o translate.s

$ gcc --version
gcc (Ubuntu/Linaro 4.5.2-2ubuntu1) 4.5.2
Copyright (C) 2010 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
$

The OOM comes while cc1 is writing the output file out to disk; strace shows a large number of writes interspersed with calls to mmap2() requesting 1MiB allocations for every ~680-748KiB output to the file. By the time of the OOM (with ulimit now raised to 6GiB), the output file has grown to 174MiB here; but that only accounts for something like 260MiB, nothing close to the ulimit. So I'm still not sure what's going on here.