Re: Ping! Unreviewed patch (hot/cold partitioning update)

[James E Wilson <wilson at specifixinc dot com>]

Caroline Tice wrote:
>         * Makefile.in (STAGEFEEDBACK_FLAGS_TO_PASS) Add
>         "-freorder-blocks-and-partition" to the flags used in second
>         stage of profiledbootstrap.

This breaks profiledbootstrap on linux, and any other target that 
defaults to DWARF2 debug info.

There is a warning emitted in opts.c if -g is used with
-freorder-blocks-and-partition, and the current debug info format is 
DWARF2.  -g is a default option for BOOT_CFLAGS.  STAGE2_FLAGS_TO_PASS 
includes -Werror, which turns warnings into errors.  So the stage2 build 
includes the combination -g -freorder-blocks-and-partition -Werror which 
is an error for any target that defaults to DWARF2 debug info.

I think the right fix here is to remove -freorder-blocks-and-partition 
from STAGEFEEDBACK_FLAGS_TO_PASS in Makefile.in, until such time as we 
have complete support for it, i.e. DWARF2 support.

By the way, the fact that your patch uses DWARF_DEBUG is also a bug, as 
the dwarf v1 support is now gone.  However, this is a different problem. 
 I see we still have quite a few DWARF_DEBUG and DWARF_DEBUGGING_INFO 
references floating around in various files, all of which are now 
obsolete.  If this stuff was gone, you would have noticed the problem 
before checking in your patch.  We can deal with this problem in a 
separate patch.

The attached patch was tested with an x86_64 make profiledbootstrap.  It 
dies while building the -fprofile-use dwarf2out.o file, but that is a 
lot farther than it gets without this patch.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com

2004-08-23  James E Wilson  <wilson@specifixinc.com>

	* Makefile.in (STAGEFEEDBACK_FLAGS_TO_PASS): Remove
	-freorder-blocks-and-partition.

Index: Makefile.in
===================================================================
RCS file: /cvs/gcc/gcc/gcc/Makefile.in,v
retrieving revision 1.1352
diff -p -p -r1.1352 Makefile.in
*** Makefile.in	18 Aug 2004 22:41:53 -0000	1.1352
--- Makefile.in	24 Aug 2004 02:43:31 -0000
*************** STAGEPROFILE_FLAGS_TO_PASS = \
*** 3601,3607 ****
  # Files never linked into the final executable produces warnings about missing
  # profile.
  STAGEFEEDBACK_FLAGS_TO_PASS = \
! 	CFLAGS="$(BOOT_CFLAGS) -fprofile-use -freorder-blocks-and-partition"
  
  # Only build the C compiler for stage1, because that is the only one that
  # we can guarantee will build with the native compiler, and also it is the
--- 3601,3607 ----
  # Files never linked into the final executable produces warnings about missing
  # profile.
  STAGEFEEDBACK_FLAGS_TO_PASS = \
! 	CFLAGS="$(BOOT_CFLAGS) -fprofile-use"
  
  # Only build the C compiler for stage1, because that is the only one that
  # we can guarantee will build with the native compiler, and also it is the