[PATCH] selftest.c: gracefully handle NULL in assert_streq

[Jeff Law]

On 07/19/2016 07:04 AM, David Malcolm wrote:
> If a NULL is passed in as the expected or actual value for an
> ASSERT_STREQ, the call to strcmp within selftest::assert_streq
> can segfault, leading to a failure of -fself-test without
> indicating which test failed.
>
> Handle this more gracefully by checking for NULL, so that
> information on the failing test is printed to stderr if this
> occurs.
>
> Successfully bootstrapped&regrtested on x86_64-pc-linux-gnu.
> I also manually tested the various kinds of failure of
> ASSERT_STR_EQ, and verified that each branch prints a sane
> failure message before aborting.
>
> OK for trunk?
>
> gcc/ChangeLog:
> 	* selftest.c (selftest::assert_streq): Handle NULL values of
> 	val_actual and val_expected.
OK.
jeff