re PR debug/39086 (ICE in decl_ultimate_origin, at dwarf2out.c:5770 when compiling with -fno-tree-sra)

        PR debug/39086
        * tree-nrv.c (tree_nrv): Don't do this optimization if the front
        end already did.  Notice GIMPLE_CALL modifications of the result.
        Don't copy debug information from an ignored decl or a decl from
        another function.

From-SVN: r144772