middle-end/114299 - missing error recovery from gimplify failure

middle-end/114299 - missing error recovery from gimplify failure

When internal_get_tmp_var fails to gimplify the value the temporary
SSA name is supposed to be initialized with we can leak SSA names
with a NULL SSA_NAME_DEF_STMT into the IL.  That's bad, so recover
from this by instead returning a decl in that case.

	PR middle-end/114299
	* gimplify.cc (internal_get_tmp_var): When gimplification
	of VAL failed, return a decl.

	* gcc.target/i386/pr114299.c: New testcase.