RFC: fix PR gdb/15538

Tom Tromey
2013-04-15T19:36:01Z

This fixes PR 15538, an assertion failure when reading a certain file.

The bug is that dwarf2_record_block_ranges asserts that the ranges
section has been read in -- but it can be called without this occurring.

The fix is to simply read in the section in dwarf2_record_block_ranges.

I didn't know how to make a test case, so I haven't provided one.
If this is an issue I will try harder to figure it out.

Built and regtested on x86-64 Fedora 18.
The bug reporter also tested it.

Tom

PR gdb/15538:
* dwarf2read.c (dwarf2_record_block_ranges): Ensure that the
ranges section has been read.

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 8947f8f..64fc7da 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -10458,7 +10458,7 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block,
address range list in the .debug_ranges section. */
unsigned long offset = (DW_UNSND (attr)
+ (need_ranges_base ? cu->ranges_base : 0));
- const gdb_byte *buffer = dwarf2_per_objfile->ranges.buffer + offset;
+ const gdb_byte *buffer;

/* For some target architectures, but not others, the
read_address function sign-extends the addresses it returns.
@@ -10477,7 +10477,7 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block,
CORE_ADDR base = cu->base_address;
int base_known = cu->base_known;

- gdb_assert (dwarf2_per_objfile->ranges.readin);
+ dwarf2_read_section (objfile, &dwarf2_per_objfile->ranges);
if (offset >= dwarf2_per_objfile->ranges.size)
{
complaint (&symfile_complaints,
@@ -10485,6 +10485,7 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block,
offset);
return;
}
+ buffer = dwarf2_per_objfile->ranges.buffer + offset;

for (;;)
{