This is the mail archive of the
gdb-cvs@sourceware.org
mailing list for the GDB project.
src/gdb ChangeLog dwarf2read.c testsuite/Chang ...
- From: brobecke at sourceware dot org
- To: gdb-cvs at sourceware dot org
- Date: 18 Mar 2010 18:35:55 -0000
- Subject: src/gdb ChangeLog dwarf2read.c testsuite/Chang ...
CVSROOT: /cvs/src
Module name: src
Changes by: brobecke@sourceware.org 2010-03-18 18:35:55
Modified files:
gdb : ChangeLog dwarf2read.c
gdb/testsuite : ChangeLog
Added files:
gdb/testsuite/gdb.dwarf2: dw2-anonymous-func.S
dw2-anonymous-func.exp
Log message:
[dwarf] Anonymous nested function causes SEGV during psymbol read
According to the DWARF3 standard, a function always has a name attribute
(Section 3.3 - Subroutine and Entry Point Entries). The only exception
is when a DW_AT_abstract_origin attribute is provided, in which case
the name may be inherited from the referenced DIE.
The problem occured because our compiler generated a subprogram DIE
for a nested function where the name attribute was missing (and no
abstract-origin either). Our code in add_partial_symbol is not
prepared to deal with the situation, and happily just tries to compute
the length of the (NULL) function name.
This normally cannot happen, because there is already a guard in
scan_partial_symbols, where we (silently!) ignore anonymous dies,
including anonymous subprograms. Unfortunately, there is a flaw that
affects Ada and other languages that allow nested subprograms. For
nested subprograms, we do not go through scan_partial_symbols and
thus we are missing the name check.
This patch adds the name check in the nested subprogram case. It also
adds a complaint which is emitted during the psymtab->symtab conversion
phase.
gdb/ChangeLog:
* dwarf2read.c (add_partial_subprogram): Make sure the subprogram
DIE has a name before creating the associated partial symbol.
(read_func_scope): Emit a complaint if the subprogram does not
have a name or when we can't extract the subprogram PC bounds.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-anonymous-func.S: New file.
* gdb.dwarf2/dw2-anonymous-func.exp: New testcase.
Tested on x86_64-linux, no regression. Note that the testcase also
verifies that the psymtab->symtab conversion does not crash (this is
the purpose of the "list file1.txt:1" test.
Patches:
http://sourceware.org/cgi-bin/cvsweb.cgi/src/gdb/ChangeLog.diff?cvsroot=src&r1=1.11502&r2=1.11503
http://sourceware.org/cgi-bin/cvsweb.cgi/src/gdb/dwarf2read.c.diff?cvsroot=src&r1=1.370&r2=1.371
http://sourceware.org/cgi-bin/cvsweb.cgi/src/gdb/testsuite/ChangeLog.diff?cvsroot=src&r1=1.2181&r2=1.2182
http://sourceware.org/cgi-bin/cvsweb.cgi/src/gdb/testsuite/gdb.dwarf2/dw2-anonymous-func.S.diff?cvsroot=src&r1=NONE&r2=1.1
http://sourceware.org/cgi-bin/cvsweb.cgi/src/gdb/testsuite/gdb.dwarf2/dw2-anonymous-func.exp.diff?cvsroot=src&r1=NONE&r2=1.1