Patches for egcs/OSR5 Was: controlling exception type per target

[Robert Lipe <robertl at dgii dot com>]

> Sorry I haven't gotten back to you before.  

'Tis quite OK.  I'm glad I waited for your reply, becuase I was 
indeed headed down a bad path.    Your suggestions took me where
I needed to go.  Thanx, Jason!

> I think this should be handled
> by setting up exceptions_via_longjmp in main(), with a simple
> 
> #ifdef DWARF2_UNWIND_INFO
> exceptions_via_longjmp = DWARF2_UNWIND_INFO;
> #endif

The negative logic definitions took a while for me to grok.

I'll leave submitting/applying that patch to you.   I stuck it in 
my copy in what seemed like an OK place.  It is required.   

*** toplev.c_   Mon Sep 15 21:07:28 1997
--- toplev.c    Wed Oct  1 22:47:54 1997
***************
*** 4289,4294 ****
--- 4289,4298 ----
    OVERRIDE_OPTIONS;
  #endif

+ #ifdef DWARF2_UNWIND_INFO
+   exceptions_via_longjmp = DWARF2_UNWIND_INFO ;
+ #endif
+
    if (profile_block_flag == 3)
      {
        warning ("`-ax' and `-a' are conflicting options. `-a' ignored.");


> > Should I expand this scheme on into crtstuff as well?
> 
> You can tell whether you are doing COFF or ELF with #ifdefs, right?  I
> would think you could special-case the SCO tm.h so that when CRT_BEGIN or
> CRT_END are defined, you use unconditional defines.  irix6.h does something
> similar for n32/n64 multilibbing.

You could.   I think I've found that if I just let crtstuff spill
the eh sections, it's OK as long as I pick a name that makes the 
assembler not vomit.  It seems that they're never referenced.  I decided
to go ahead and put the scaffolding for EH_FRAMEs in for COFF in case
they come in handy in the future.

I haven't rerun the full make bootstrap/runtest with it, but I did
do a 'make bootstrap3 followed by a 

nice runtest --outdir ${COFFDIR} --tool g++  \
        --srcdir ${SRC}/gcc/testsuite \
        --target_board 'unix{-mcoff,-melf}' \
        GXX_UNDER_TEST=negcs \
        CXXFLAGS="-g -O" \
        old-deja.exp=eh*
 
and got really promising results:

Test Run By robertl on Thu Oct  2 00:41:57 1997
Native configuration is i586-pc-sco3.2v5.0.4

                === g++ tests ===

Running target unix/-mcoff
Running /play/egcs-970917/gcc/testsuite/g++.old-deja/old-deja.exp ...

                === g++ Summary for unix/-mcoff ===

# of expected passes            103
Running target unix/-melf
Running /play/egcs-970917/gcc/testsuite/g++.old-deja/old-deja.exp ...

                === g++ Summary for unix/-melf ===

# of expected passes            103

                === g++ Summary ===

# of expected passes            206
negcs version egcs-2.90.11 970929 (gcc2-970802 experimental)



So please consider this patch for inclusion:


Thu Oct  2 00:30:15 1997  Robert Lipe (robertl@dgii.com)

	* sco5.h: Let ELF use dwarf2 unwinding.  COFF uses sjlj
	(EH_FRAME_SECTION_ASM_OP, EH_FRAME_SECTION_ASM_OP_ELF): Defined.
	(EH_FRAME_SECTION_ASM_OP_COFF): Likewise.
	(DWARF2_UNWIND_INFO): Let this track object file format.
	(EXTRA_SECTIONS): Add in_eh.
	(EH_FRAME_SECTION_ASM_OP, EH_FRAME_SECTION_ASM_OP_ELF, EH_FRAME_SECTION_ASM_OP_COFF): defined


*** config/i386/sco5.h_	Wed Oct  1 22:35:32 1997
--- config/i386/sco5.h	Wed Oct  1 23:17:35 1997
***************
*** 76,81 ****
--- 76,92 ----
  #undef GLOBAL_ASM_OP
  #define GLOBAL_ASM_OP			"\t.globl"
  
+ #undef EH_FRAME_SECTION_ASM_OP
+ #define EH_FRAME_SECTION_ASM_OP_COFF	"\t.section\t.ehfram, \"x\""
+ #define EH_FRAME_SECTION_ASM_OP_ELF	"\t.section\t.eh_frame, \"aw\""
+ #define EH_FRAME_SECTION_ASM_OP	\
+   ((TARGET_ELF) ? EH_FRAME_SECTION_ASM_OP_ELF : EH_FRAME_SECTION_ASM_OP_COFF)
+ 
+ /* Avoid problems (long sectino names, forward assembler refs) with DWARF
+    exception unwinding when we're generating COFF */
+ #define DWARF2_UNWIND_INFO	\
+   ((TARGET_ELF) ? 1 : 0 )  
+ 
  #undef CONST_SECTION_ASM_OP
  #define CONST_SECTION_ASM_OP_COFF	"\t.section\t.rodata, \"x\""
  #define CONST_SECTION_ASM_OP_ELF	"\t.section\t.rodata"
***************
*** 563,569 ****
    ((TARGET_ELF) ? DWARF_DEBUG: SDB_DEBUG)
  
  #undef EXTRA_SECTIONS
! #define EXTRA_SECTIONS in_const, in_init, in_fini, in_ctors, in_dtors
  
  #undef EXTRA_SECTION_FUNCTIONS
  #define EXTRA_SECTION_FUNCTIONS						\
--- 574,580 ----
    ((TARGET_ELF) ? DWARF_DEBUG: SDB_DEBUG)
  
  #undef EXTRA_SECTIONS
! #define EXTRA_SECTIONS in_const, in_init, in_fini, in_ctors, in_dtors, in_eh
  
  #undef EXTRA_SECTION_FUNCTIONS
  #define EXTRA_SECTION_FUNCTIONS						\
***************
*** 901,906 ****
--- 912,918 ----
  # undef FINI_SECTION_ASM_OP
  # undef CTORS_SECTION_ASM_OP
  # undef DTORS_SECTION_ASM_OP
+ # undef EH_FRAME_SECTION_ASM_OP
  # undef CTOR_LIST_BEGIN
  # undef CTOR_LIST_END
  # undef DO_GLOBAL_CTORS_BODY
***************
*** 912,922 ****
--- 924,936 ----
  #  define FINI_SECTION_ASM_OP FINI_SECTION_ASM_OP_ELF
  #  define DTORS_SECTION_ASM_OP DTORS_SECTION_ASM_OP_ELF
  #  define CTORS_SECTION_ASM_OP CTORS_SECTION_ASM_OP_ELF
+ #  define EH_FRAME_SECTION_ASM_OP EH_FRAME_SECTION_ASM_OP_ELF
  # else /* ! _SCO_ELF */
  #  define INIT_SECTION_ASM_OP INIT_SECTION_ASM_OP_COFF
  #  define FINI_SECTION_ASM_OP FINI_SECTION_ASM_OP_COFF
  #  define DTORS_SECTION_ASM_OP DTORS_SECTION_ASM_OP_COFF
  #  define CTORS_SECTION_ASM_OP CTORS_SECTION_ASM_OP_COFF
+ #  define EH_FRAME_SECTION_ASM_OP ""
  #  define CTOR_LIST_BEGIN asm (INIT_SECTION_ASM_OP); asm ("pushl $0")
  #  define CTOR_LIST_END CTOR_LIST_BEGIN
  #  define DO_GLOBAL_CTORS_BODY						\