* frags.c (frag_init): Call obstack_begin on `frags'.

* frags.c (frag_init): Call obstack_begin on `frags'.
* subsegs.c (subsegs_begin): Don't do it here.
* as.c (main): Call frag_init before subsegs_begin.

* frags.c (frag_append_1_char): New function.
* frags.h (frag_append_1_char): Declare it.
(FRAG_APPEND_1_CHAR): Call it.  Old definition is commented out for now.

* as.h (struct frag): Added (but commented out) new fields for tracking current
alignment.
(frag_now_fix): Changed macro to function declaration.
* frags.c (frag_now_fix): Define function here.
(frag_new): Use it instead of accessing `frags' directly.
* frags.h (frags): Change comment to indicate it shouldn't be accessed directly.
* subsegs.h (struct frchain): New field frch_obstack, intended to eventually
replace global `frags' obstack.
* subsegs.c (subseg_set_rest): Use frag_now_fix instead of accessing `frags'
directly.  Initialize fields of new frchainS explicitly instead of with memset.
* config/obj-coff.c (obj_coff_ln) [!BFD_ASSEMBLER]: Use frag_now_fix.
* config/tc-mips.c (s_loc), config/obj-vms.c (vms_resolve_symbol_redef),
symbols.c (colon): Likewise.