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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


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