trans-common.c (create_common): Add decl to function chain to preserve identifier scope in debug output.

	* fortran/trans-common.c (create_common):  Add decl to function
	chain to preserve identifier scope in debug output.

	* dbxout.c: Emit .stabs debug info for Fortran COMMON block
	variables as base symbol name + offset using N_BCOMM/N_ECOMM.
	(is_fortran, dbxout_common_name, dbxout_common_check): New functions.
	(dbxout_symbol_location): Transform N_LCSYM to N_GSYM for storage
	in common.
	(dbxout_syms): Check for COMMON-based symbol and wrap in
	N_BCOMM/N_ECOMM stab bracket, including as many symbols as possible
	in bracket for efficiency.

	* dwarf2out.c: Emit DWARF debug info for Fortran COMMON block
	using DW_TAG_common_block + member offset.
	(add_pubname_string): New function.
	(dw_expand_expr): New function to find block name and offset for
	COMMON var.
	(common_check): New function to check whether symbol in Fortran COMMON.
	(gen_variable_die): If COMMON, use DW_TAG_common_block.

	* testsuite/gcc.dg/debug/pr35154.c:  New test to check that non-Fortran
	use of common is unchanged.

	* testsuite/lib/gfortran-dg.exp:  New harness to compile Fortran progs
	with all combinations of debug options available on target.
	* testsuite/gfortran.dg/debug/debug.exp:  Ditto.
	* testsuite/gfortran.dg/debug/trivial.f:  Ditto.
	* testsuite/gfortran.dg/debug/pr35154-stabs.f:  New test case for
	.stabs functionality.
	* testsuite/gfortran.dg/debug/pr35154-dwarf2.f:  New test case for
	DWARF functionality.

From-SVN: r133801