xref: /openbsd/gnu/usr.bin/binutils/gdb/PROBLEMS (revision 7b36286a)
1
2			Known problems in GDB 6.3
3
4		See also: http://www.gnu.org/software/gdb/bugs/
5
6
7*** Build problems
8
9build/1411: build fails on hpux 10.20 and hpux 11.00 with CMA threads
10
11GDB does not build on HP/UX 10.20 or HP/UX 11.00 if the CMA
12thread package is installed.  The compile error is:
13
14  ../../gdb/hpux-thread.c:222: variable-size type declared outside of any function
15
16This happens only if the CMA thread package is installed.
17
18As a workaround, you can disable support for CMA threads
19by editing the file gdb/configure.  Find the line:
20
21  if test -f /usr/include/dce/cma_config.h ; then
22
23And replace it with:
24
25  if false ; then
26
27*** Misc
28
29gdb/1560: Control-C does not always interrupt GDB.
30
31When GDB is busy processing a command which takes a long time to
32complete, hitting Control-C does not have the expected effect.
33The command execution is not aborted, and the "QUIT" message confirming
34the abortion is displayed only after the command has been completed.
35
36*** C++ support
37
38gdb/931: GDB could be more generous when reading types C++ templates on input
39
40When the user types a template, GDB frequently requires the type to be
41typed in a certain way (e.g. "const char*" as opposed to "const char *"
42or "char const *" or "char const*").
43
44gdb/1512: no canonical way to output names of C++ types
45
46We currently don't have any canonical way to output names of C++ types.
47E.g. "const char *" versus "char const *"; more subtleties arise when
48dealing with templates.
49
50gdb/1516: [regression] local classes, gcc 2.95.3, dwarf-2
51
52With gcc 2.95.3 and the dwarf-2 debugging format, classes which are
53defined locally to a function include the demangled name of the function
54as part of their name.  For example, if a function "foobar" contains a
55local class definition "Local", gdb will say that the name of the class
56type is "foobar__Fi.0:Local".
57
58This applies only to classes where the class type is defined inside a
59function, not to variables defined with types that are defined somewhere
60outside any function (which most types are).
61
62gdb/1588: names of c++ nested types in casts must be enclosed in quotes
63
64You must type
65  (gdb) print ('Foo::Bar') x
66or
67  (gdb) print ('Foo::Bar' *) y
68instead of
69  (gdb) print (Foo::Bar) x
70or
71  (gdb) print (Foo::Bar *) y
72respectively.
73
74gdb/1091: Constructor breakpoints ignored
75gdb/1193: g++ 3.3 creates multiple constructors: gdb 5.3 can't set breakpoints
76
77When gcc 3.x compiles a C++ constructor or C++ destructor, it generates
782 or 3 different versions of the object code.  These versions have
79unique mangled names (they have to, in order for linking to work), but
80they have identical source code names, which leads to a great deal of
81confusion.  Specifically, if you set a breakpoint in a constructor or a
82destructor, gdb will put a breakpoint in one of the versions, but your
83program may execute the other version.  This makes it impossible to set
84breakpoints reliably in constructors or destructors.
85
86gcc 3.x generates these multiple object code functions in order to
87implement virtual base classes.  gcc 2.x generated just one object code
88function with a hidden parameter, but gcc 3.x conforms to a multi-vendor
89ABI for C++ which requires multiple object code functions.
90
91*** Threads
92
93threads/1650: manythreads.exp
94
95On GNU/Linux systems that use the old LinuxThreads thread library, a
96program rapidly creating and deleting threads can confuse GDB leading
97to an internal error.
98
99This problem does not occur on newer systems that use the NPTL
100library, and did not occur with GDB 6.1.
101