support for compilation units with discontiguous address ranges? (.debug_ranges)

[Brian Grant <grant at transmeta dot com>]

Has anyone implemented dwarf2 support in gdb for compilation units with 
discontiguous ranges of addresses?  gcc 3.x doesn't seem to produce
.debug_ranges and gdb 5.0 doesn't read it at all. gdb also seems to
ignore .debug_aranges.

What I've tried to do is to put different functions in the same C file into 
different text sections using gcc as follows:

foobar.c:
__attribute__((section(".text1"))) void foo() {...}
__attribute__((section(".text2"))) void bar() {...}

In the executable, they are located something like:

Sections:
Idx Name          Size      VMA       LMA       File off  Algn
...
  2 .text1        0000a688  00ec5800  00ec5800  000001b4  2**10
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  3 .text2        0000ee58  00ed5800  00ed5800  0000a83c  2**10
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
...

What currently happens in gdb is that all functions in .text1 
and .text2 at addresses between foo() and bar() are attributed
the file and line number of the last line of foo(). Their real,
accurate line-number info is overshadowed completely.

I noticed that gcc doesn't produce DW_AT_low_pc/high_pc fields for
foobar.c, as it normally would for a DW_TAG_compilation_unit record,
where all functions in the compilation unit were in the same section.
Does anyone know of a workaround for this problem?

--Brian Grant
  Transmeta Corp.