[Bug sanitizer/71480] ASan should align string constants to shadow granularity.

["m.ostapenko at samsung dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71480

--- Comment #1 from Maxim Ostapenko <m.ostapenko at samsung dot com> ---
The problem appears for arm target only, x86 is fine.

$ armv7l-tizen-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=armv7l-tizen-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/home/max/install/armv7l-tizen/libexec/gcc/armv7l-tizen-linux-gnueabi/7.0.0/lto-wrapper
Target: armv7l-tizen-linux-gnueabi
Configured with: /home/max/workspace/downloads/gcc/configure
--prefix=/home/max/install/armv7l-tizen --build=x86_64-pc-linux-gnu
--host=x86_64-pc-linux-gnu --target=armv7l-tizen-linux-gnueabi --disable-nls
--enable-poison-system-directories
--with-pkgversion=Tizen.armv7l.GA2.2015-08-26
--with-sysroot=/home/max/install/armv7l-tizen/armv7l-tizen-linux-gnueabi/sys-root
--with-gmp=/home/max/build/v6/fake-root
--with-libelf=/home/max/build/v6/fake-root
--with-mpc=/home/max/build/v6/fake-root
--with-mpfr=/home/max/build/v6/fake-root --without-cloog --without-ppl
--with-host-libstdcxx='-static-libgcc -Wl,-Bstatic,-lstdc++,-Bdynamic -lm'
--enable-languages=c,c++,fortran --disable-libstdcxx-pch --enable-__cxa_atexit
--enable-libssp --enable-lto --enable-checking=release
--with-build-time-tools=/home/max/install/armv7l-tizen/bin --with-gnu-as
--with-gnu-ld
--with-specs='%{funwind-tables|fno-unwind-tables|mabi=*|ffreestanding|nostdlib:;:-funwind-tables}
%{!Werror=unused-local-typedefs:%{!Wno-error=unused-local-typedefs:-Wno-error=unused-local-typedefs}}
%{fuse-linker-plugin|fno-use-linker-plugin|flto|flto=*:;:-fno-use-linker-plugin}'
--disable-multilib --disable-gnu-unique-object --enable-linker-build-id
--with-mode=arm --with-fpu=neon-vfpv4 --with-tune=cortex-a8 --with-float=softfp
--enable-libgomp --enable-linux-futex
Thread model: posix
gcc version 7.0.0 20160607 (experimental) (Tizen.armv7l.GA2.2015-08-26)