[deliverable/binutils-gdb.git] / gdb / PROBLEMS


			Known problems in GDB 6.1

		See also: http://www.gnu.org/software/gdb/bugs/

mips*-*-*
powerpc*-*-*
sparc*-*-*

GDB's SPARC, MIPS and PowerPC targets, in 6.0, have not been updated
to use the new frame mechanism.

People encountering problems with these targets should consult GDB's
web pages and mailing lists (http://www.gnu.org/software/gdb/) to see
if there is an update.

arm-*-*

GDB's ARM target, in 6.0, has not been updated to use the new frame
mechanism.

Fortunately the ARM target, in the GDB's mainline sources, has been
updated so people encountering problems should consider downloading a
more current GDB (http://www.gnu.org/software/gdb/current).

gdb/1516: [regression] local classes, gcc 2.95.3, dwarf-2

With gcc 2.95.3 and the dwarf-2 debugging format, classes which are
defined locally to a function include the demangled name of the function
as part of their name.  For example, if a function "foobar" contains a
local class definition "Local", gdb will say that the name of the class
type is "foobar__Fi.0:Local".

This applies only to classes where the class type is defined inside a
function, not to variables defined with types that are defined somewhere
outside any function (which most types are).

gdb/1091: Constructor breakpoints ignored
gdb/1193: g++ 3.3 creates multiple constructors: gdb 5.3 can't set breakpoints

When gcc 3.x compiles a C++ constructor or C++ destructor, it generates
2 or 3 different versions of the object code.  These versions have
unique mangled names (they have to, in order for linking to work), but
they have identical source code names, which leads to a great deal of
confusion.  Specifically, if you set a breakpoint in a constructor or a
destructor, gdb will put a breakpoint in one of the versions, but your
program may execute the other version.  This makes it impossible to set
breakpoints reliably in constructors or destructors.

gcc 3.x generates these multiple object code functions in order to
implement virtual base classes.  gcc 2.x generated just one object code
function with a hidden parameter, but gcc 3.x conforms to a multi-vendor
ABI for C++ which requires multiple object code functions.

gdb/1560: Control-C does not always interrupt GDB.
When GDB is busy processing a command which takes a long time to
complete, hitting Control-C does not have the expected effect.
The command execution is not aborted, and the "QUIT" message confirming
the abortion is displayed only after the command has been completed.
Commit	Line	Data
e2c9a72c	1
faae5abe	2	Known problems in GDB 6.1
e2c9a72c	3
36cc83a3	4	See also: http://www.gnu.org/software/gdb/bugs/
e2c9a72c	5
e6beb428 AC	6	mips--*
	7	powerpc--*
	8	sparc--*
	9
	10	GDB's SPARC, MIPS and PowerPC targets, in 6.0, have not been updated
	11	to use the new frame mechanism.
	12
	13	People encountering problems with these targets should consult GDB's
	14	web pages and mailing lists (http://www.gnu.org/software/gdb/) to see
	15	if there is an update.
	16
	17	arm--
	18
	19	GDB's ARM target, in 6.0, has not been updated to use the new frame
	20	mechanism.
	21
ce2826aa	22	Fortunately the ARM target, in the GDB's mainline sources, has been
e6beb428 AC	23	updated so people encountering problems should consider downloading a
	24	more current GDB (http://www.gnu.org/software/gdb/current).
	25
c6e06ede MC	26	gdb/1516: [regression] local classes, gcc 2.95.3, dwarf-2
	27
	28	With gcc 2.95.3 and the dwarf-2 debugging format, classes which are
	29	defined locally to a function include the demangled name of the function
	30	as part of their name. For example, if a function "foobar" contains a
	31	local class definition "Local", gdb will say that the name of the class
	32	type is "foobar__Fi.0:Local".
	33
	34	This applies only to classes where the class type is defined inside a
	35	function, not to variables defined with types that are defined somewhere
	36	outside any function (which most types are).
	37
e8ac10a6 MC	38	gdb/1091: Constructor breakpoints ignored
e8ac10a6 MC	39	gdb/1193: g++ 3.3 creates multiple constructors: gdb 5.3 can't set breakpoints
e2c9a72c	40
e8ac10a6 MC	41	When gcc 3.x compiles a C++ constructor or C++ destructor, it generates
	42	2 or 3 different versions of the object code. These versions have
	43	unique mangled names (they have to, in order for linking to work), but
	44	they have identical source code names, which leads to a great deal of
	45	confusion. Specifically, if you set a breakpoint in a constructor or a
	46	destructor, gdb will put a breakpoint in one of the versions, but your
	47	program may execute the other version. This makes it impossible to set
	48	breakpoints reliably in constructors or destructors.
	49
	50	gcc 3.x generates these multiple object code functions in order to
	51	implement virtual base classes. gcc 2.x generated just one object code
	52	function with a hidden parameter, but gcc 3.x conforms to a multi-vendor
	53	ABI for C++ which requires multiple object code functions.
589ca796 JB	54
	55	gdb/1560: Control-C does not always interrupt GDB.
	56	When GDB is busy processing a command which takes a long time to
	57	complete, hitting Control-C does not have the expected effect.
	58	The command execution is not aborted, and the "QUIT" message confirming
	59	the abortion is displayed only after the command has been completed.