* Conditions:: Break conditions
* Break Commands:: Breakpoint command lists
* Save Breakpoints:: How to save breakpoints in a file
+* Static Probe Points:: Listing static probe points
* Error in Breakpoints:: ``Cannot insert breakpoints''
* Breakpoint-related Warnings:: ``Breakpoint address adjusted...''
@end menu
that can no longer be recreated.
@end table
+@node Static Probe Points
+@subsection Static Probe Points
+
+@cindex static probe point, SystemTap
+@value{GDBN} supports @dfn{SDT} probes in the code. @acronym{SDT} stands
+for Statically Defined Tracing, and the probes are designed to have a tiny
+runtime code and data footprint, and no dynamic relocations. They are
+usable from assembly, C and C@t{++} languages. See
+@uref{http://sourceware.org/systemtap/wiki/UserSpaceProbeImplementation}
+for a good reference on how the @acronym{SDT} probes are implemented.
+
+Currently, @code{SystemTap} (@uref{http://sourceware.org/systemtap/})
+@acronym{SDT} probes are supported on ELF-compatible systems. See
+@uref{http://sourceware.org/systemtap/wiki/AddingUserSpaceProbingToApps}
+for more information on how to add @code{SystemTap} @acronym{SDT} probes
+in your applications.
+
+@cindex semaphores on static probe points
+Some probes have an associated semaphore variable; for instance, this
+happens automatically if you defined your probe using a DTrace-style
+@file{.d} file. If your probe has a semaphore, @value{GDBN} will
+automatically enable it when you specify a breakpoint using the
+@samp{-probe-stap} notation. But, if you put a breakpoint at a probe's
+location by some other method (e.g., @code{break file:line}), then
+@value{GDBN} will not automatically set the semaphore.
+
+You can examine the available static static probes using @code{info
+probes}, with optional arguments:
+
+@table @code
+@kindex info probes
+@item info probes stap @r{[}@var{provider} @r{[}@var{name} @r{[}@var{objfile}@r{]}@r{]}@r{]}
+If given, @var{provider} is a regular expression used to match against provider
+names when selecting which probes to list. If omitted, probes by all
+probes from all providers are listed.
+
+If given, @var{name} is a regular expression to match against probe names
+when selecting which probes to list. If omitted, probe names are not
+considered when deciding whether to display them.
+
+If given, @var{objfile} is a regular expression used to select which
+object files (executable or shared libraries) to examine. If not
+given, all object files are considered.
+
+@item info probes all
+List the available static probes, from all types.
+@end table
+
+@vindex $_probe_arg@r{, convenience variable}
+A probe may specify up to twelve arguments. These are available at the
+point at which the probe is defined---that is, when the current PC is
+at the probe's location. The arguments are available using the
+convenience variables (@pxref{Convenience Vars})
+@code{$_probe_arg0}@dots{}@code{$_probe_arg11}. Each probe argument is
+an integer of the appropriate size; types are not preserved. The
+convenience variable @code{$_probe_argc} holds the number of arguments
+at the current probe point.
+
+These variables are always available, but attempts to access them at
+any location other than a probe point will cause @value{GDBN} to give
+an error message.
+
+
@c @ifclear BARETARGET
@node Error in Breakpoints
@subsection ``Cannot insert breakpoints''
functions with identical names in different source files.
@end table
+@cindex breakpoint at static probe point
+@item -pstap|-probe-stap @r{[}@var{objfile}:@r{[}@var{provider}:@r{]}@r{]}@var{name}
+The @sc{gnu}/Linux tool @code{SystemTap} provides a way for
+applications to embed static probes. @xref{Static Probe Points}, for more
+information on finding and using static probes. This form of linespec
+specifies the location of such a static probe.
+
+If @var{objfile} is given, only probes coming from that shared library
+or executable matching @var{objfile} as a regular expression are considered.
+If @var{provider} is given, then only probes from that provider are considered.
+If several probes match the spec, @value{GDBN} will insert a breakpoint at
+each one of those probes.
+
@end table
The variable @code{$_exitcode} is automatically set to the exit code when
the program being debugged terminates.
+@item $_probe_argc
+@itemx $_probe_arg0@dots{}$_probe_arg11
+Arguments to a static probe. @xref{Static Probe Points}.
+
@item $_sdata
@vindex $_sdata@r{, inspect, convenience variable}
The variable @code{$_sdata} contains extra collected static tracepoint
Collect the return address. This is helpful if you want to see more
of a backtrace.
+@item $_probe_argc
+Collects the number of arguments from the static probe at which the
+tracepoint is located.
+@xref{Static Probe Points}.
+
+@item $_probe_arg@var{n}
+@var{n} is an integer between 0 and 11. Collects the @var{n}th argument
+from the static probe at which the tracepoint is located.
+@xref{Static Probe Points}.
+
@item $_sdata
@vindex $_sdata@r{, collect}
Collect static tracepoint marker specific data. Only available for
@node Supported Languages
@section Supported Languages
-@value{GDBN} supports C, C@t{++}, D, Objective-C, Fortran, Java, OpenCL C, Pascal,
-assembly, Modula-2, and Ada.
+@value{GDBN} supports C, C@t{++}, D, Go, Objective-C, Fortran, Java,
+OpenCL C, Pascal, assembly, Modula-2, and Ada.
@c This is false ...
Some @value{GDBN} features may be used in expressions regardless of the
language you use: the @value{GDBN} @code{@@} and @code{::} operators,
@menu
* C:: C and C@t{++}
* D:: D
+* Go:: Go
* Objective-C:: Objective-C
* OpenCL C:: OpenCL C
* Fortran:: Fortran
GDC, LDC or DMD compilers. Currently @value{GDBN} supports only one D
specific feature --- dynamic arrays.
+@node Go
+@subsection Go
+
+@cindex Go (programming language)
+@value{GDBN} can be used to debug programs written in Go and compiled with
+@file{gccgo} or @file{6g} compilers.
+
+Here is a summary of the Go-specific features and restrictions:
+
+@table @code
+@cindex current Go package
+@item The current Go package
+The name of the current package does not need to be specified when
+specifying global variables and functions.
+
+For example, given the program:
+
+@example
+package main
+var myglob = "Shall we?"
+func main () @{
+ // ...
+@}
+@end example
+
+When stopped inside @code{main} either of these work:
+
+@example
+(gdb) p myglob
+(gdb) p main.myglob
+@end example
+
+@cindex builtin Go types
+@item Builtin Go types
+The @code{string} type is recognized by @value{GDBN} and is printed
+as a string.
+
+@cindex builtin Go functions
+@item Builtin Go functions
+The @value{GDBN} expression parser recognizes the @code{unsafe.Sizeof}
+function and handles it internally.
+
+@cindex restrictions on Go expressions
+@item Restrictions on Go expressions
+All Go operators are supported except @code{&^}.
+The Go @code{_} ``blank identifier'' is not supported.
+Automatic dereferencing of pointers is not supported.
+@end table
+
@node Objective-C
@subsection Objective-C
@menu
* i386::
-* A29K::
* Alpha::
* MIPS::
* HPPA:: HP PA architecture
from functions.
@end table
-@node A29K
-@subsection A29K
-
-@table @code
-
-@kindex set rstack_high_address
-@cindex AMD 29K register stack
-@cindex register stack, AMD29K
-@item set rstack_high_address @var{address}
-On AMD 29000 family processors, registers are saved in a separate
-@dfn{register stack}. There is no way for @value{GDBN} to determine the
-extent of this stack. Normally, @value{GDBN} just assumes that the
-stack is ``large enough''. This may result in @value{GDBN} referencing
-memory locations that do not exist. If necessary, you can get around
-this problem by specifying the ending address of the register stack with
-the @code{set rstack_high_address} command. The argument should be an
-address, which you probably want to precede with @samp{0x} to specify in
-hexadecimal.
-
-@kindex show rstack_high_address
-@item show rstack_high_address
-Display the current limit of the register stack, on AMD 29000 family
-processors.
-
-@end table
-
@node Alpha
@subsection Alpha
@table @code
@anchor{set auto-load safe-path}
@kindex set auto-load safe-path
-@item set auto-load safe-path @var{directories}
+@item set auto-load safe-path @r{[}@var{directories}@r{]}
Set the list of directories (and their subdirectories) trusted for automatic
loading and execution of scripts. You can also enter a specific trusted file.
+If you omit @var{directories}, @samp{auto-load safe-path} will be reset to
+its default value as specified during @value{GDBN} compilation.
+
The list of directories uses directory separator (@samp{:} on GNU and Unix
systems, @samp{;} on MS-Windows and MS-DOS) to separate directories, similarly
to the @env{PATH} environment variable.
host platform directory separator in use.
@end table
-Setting this variable to an empty string disables this security protection.
+Setting this variable to @file{/} disables this security protection.
This variable is supposed to be set to the system directories writable by the
system superuser only. Users can add their source directories in init files in
their home directories (@pxref{Home Directory Init File}). See also deprecated
You have to specify also any existing directories displayed by
by @samp{show auto-load safe-path} (such as @samp{/usr:/bin} in this example).
-@item @kbd{gdb -iex "set auto-load safe-path /usr:/bin:~/src/gdb" [@dots{}]}
+@item @kbd{gdb -iex "set auto-load safe-path /usr:/bin:~/src/gdb" @dots{}}
Specify this directory as in the previous case but just for a single
@value{GDBN} session.
-@item @kbd{gdb -iex "set auto-load safe-path" [@dots{}]}
+@item @kbd{gdb -iex "set auto-load safe-path /" @dots{}}
Disable auto-loading safety for a single @value{GDBN} session.
This assumes all the files you debug during this @value{GDBN} session will come
from trusted sources.
also suppresses any such warning messages:
@table @asis
-@item @kbd{gdb -iex "set auto-load no" [@dots{}]}
+@item @kbd{gdb -iex "set auto-load no" @dots{}}
You can use @value{GDBN} command-line option for a single @value{GDBN} session.
@item @file{~/.gdbinit}: @samp{set auto-load no}
stack.
A @code{gdb.Block} is iterable. The iterator returns the symbols
-(@pxref{Symbols In Python}) local to the block.
+(@pxref{Symbols In Python}) local to the block. Python programs
+should not assume that a specific block object will always contain a
+given symbol, since changes in @value{GDBN} features and
+infrastructure may cause symbols move across blocks in a symbol
+table.
The following block-related functions are available in the @code{gdb}
module:
@defun Symtab.fullname ()
Return the symbol table's source absolute file name.
@end defun
+
+@defun Symtab.global_block ()
+Return the global block of the underlying symbol table.
+@xref{Blocks In Python}.
+@end defun
+
+@defun Symtab.static_block ()
+Return the static block of the underlying symbol table.
+@xref{Blocks In Python}.
+@end defun
@end table
@node Breakpoints In Python
projects / deliverable / binutils-gdb.git / blobdiff