PR middle-end/37286
	* reg-stack.c (subst_stack_regs_pat) [MINUS, DIV, MULT, PLUS]:
	Initialize uninitialized input registers with a NaN.

testsuite/ChangeLog:

	PR middle-end/37286
	* gfortran.dg/pr37286.f90: New test.

From-SVN: r141603