From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) by sourceware.org (Postfix) with ESMTPS id 98C5E3838215 for ; Thu, 26 May 2022 19:42:55 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 98C5E3838215 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=palves.net Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-wr1-f50.google.com with SMTP id f2so3391421wrc.0 for ; Thu, 26 May 2022 12:42:55 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:mime-version :content-transfer-encoding; bh=+pWThuk290ce6T++zP2VYdTEW511n8WSdRNW912kdSA=; b=0uUbnDWe3HDXTN+GDS+mCVXAX3Ucal4sDKRNc2WBXDC6dh429FR+PlB5ogsTZgzfNG 7+UFldnadgKVypkP+q53qFlW+AhDZWjqazXbOs2pazMAHGq5N/ZBlR5llV1WFdP0lJM0 WzTNKev/XiG+hXvKnll51TsMpM/knOCrIUlLVvGojp/pINOIoLdsrxNmF02kaZkEBLom CBEngK+JkWsho9UveHtER8bFfWVU6v8gsY/dzOxoTdUVsK+mJqPGmsh9veLYiJeoJYYv +1HtHmGj6O9n3v6UleEeLM6TpGR5g+DY1yB3OIAL8HlGv0KymD2+gScAR4VLL2sm3dyH U5Nw== X-Gm-Message-State: AOAM530Hll3LDLGenSBmS/ukXMfMdi0how/BSoTaoks4CNf2c3lKQnju mHlRAmwXcPrDG533dxNhHWGxfSL4LhQ= X-Google-Smtp-Source: ABdhPJyjWfrvLZKkg8mrhPzPkHloInN0mGyOFlHlbqQwlsXiSmf/K5q5vA4X7qAXmOZU5M6I7AHqRA== X-Received: by 2002:a05:6000:1788:b0:20c:dfd9:b31d with SMTP id e8-20020a056000178800b0020cdfd9b31dmr31696409wrg.24.1653594172740; Thu, 26 May 2022 12:42:52 -0700 (PDT) Received: from localhost ([2001:8a0:f924:2600:209d:85e2:409e:8726]) by smtp.gmail.com with ESMTPSA id e5-20020a05600c254500b003942a244f49sm23192wma.34.2022.05.26.12.42.51 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 26 May 2022 12:42:51 -0700 (PDT) From: Pedro Alves To: gdb-patches@sourceware.org Subject: [PATCH v4] gdb/manual: Introduce location specs Date: Thu, 26 May 2022 20:42:50 +0100 Message-Id: <20220526194250.2310460-1-pedro@palves.net> X-Mailer: git-send-email 2.36.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-9.7 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, GIT_PATCH_0, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 May 2022 19:43:00 -0000 The current "Specify Location" section of the GDB manual starts with: "Several @value{GDBN} commands accept arguments that specify a location of your program's code." And then, such commands are documented as taking a "location" argument. For example, here's a representative subset: @item break @var{location} @item clear @var{location} @item until @var{location} @item list @var{location} @item edit @var{location} @itemx info line @var{location} @item info macros @var{location} @item trace @var{location} @item info scope @var{location} @item maint agent @r{[}-at @var{location}@r{,}@r{]} @var{expression} The issue here is that "location" isn't really correct for most of these commands. Instead, the "location" argument is really a placeholder that represent an umbrella term for all of the "linespecs", "explicit location", and "address location" input formats. GDB parses these and then finds the actual code locations (plural) in the program that match. For example, a "location" specified like "-function func" will actually match all the code locations in the program that correspond to the address/file/lineno of all the functions named "func" in all the loaded programs and shared libraries of all the inferiors. A location specified like "-function func -label lab" matches all the addresses of C labels named "lab" in all functions named "func". Etc. This means that several of the commands that claim they accept a "location", actually end up working with multiple locations, and the manual doesn't explain that all that well. In some cases, the command will work with all the resolved locations. In other cases, the command aborts with an error if the location specification resolves to multiple locations in the program. In other cases, GDB just arbitrarily and silently picks whatever is the first resolved code location (which sounds like should be improved). To clarify this, I propose we use the term "Location Specification", with shorthand "locaction spec", when we're talking about the user input, the argument or arguments that is/are passed to commands to instruct GDB how to find locations of interest. This is distinct from the actual code locations in the program, which are what GDB finds based on the user-specified location spec. Then use "location specification or the shorter "location spec" thoughout instead of "location" when we're talking about the user input. Thus, this commit does the following: - renames the "Specify Location" section of the manual to "Location Specifications". - It then introduces the term "Location Specification", with corresponding shorthand "location spec", as something distinct from an actual code location in the program. It explains what a concrete code location is. It explains that a location specification may be incomplete, and that it matches multiple code locations in the program. It gives examples. Most examples were moved from the "Set Breaks" section, and a couple new ones that didn't exist yet were added. I think it is better to have these centralized in this "Location Specification" section, since all the other commands that accept a location spec have an xref that points there. - Goes through the manual, and where "@var{location}" was used for a command argument, updated it to say "@var{locspec}" instead. At the same time, tweaks the description of the affected commands to describe what happens when the location spec resolves to more than one location. Most commands just did not say anything about that. One command -- "maint agent -at @var{location}" -- currently says it accepts a "location", suggesting it can accept address and explicit locations too, but that's incorrect. In reality, it only accepts linespecs, so fix it accordingly. One MI command -- "-trace-find line" -- currently says it accepts a "line specification", but it can accept address and explicit locations too, so fix it accordingly. Change-Id: Ic42ad8565e79ca67bfebb22cbb4794ea816fd08b --- gdb/doc/gdb.texinfo | 419 +++++++++++++++++++++++++------------------- gdb/doc/guile.texi | 2 +- gdb/doc/python.texi | 5 +- 3 files changed, 246 insertions(+), 180 deletions(-) diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 68679982919..6deaad88d31 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -2024,7 +2024,7 @@ func() func() (@value{GDBP}) p 'func< @end smallexample -When setting breakpoints however (@pxref{Specify Location}), you don't +When setting breakpoints however (@pxref{Location Specifications}), you don't usually need to type a quote before the function name, because @value{GDBN} understands that you want to set a breakpoint on a function: @@ -4343,17 +4343,19 @@ Vars,, Convenience Variables}, for a discussion of what you can do with convenience variables. @table @code -@item break @var{location} -Set a breakpoint at the given @var{location}, which can specify a -function name, a line number, or an address of an instruction. -(@xref{Specify Location}, for a list of all the possible ways to -specify a @var{location}.) The breakpoint will stop your program just -before it executes any of the code in the specified @var{location}. +@item break @var{locspec} +Set a breakpoint at all the code locations in your program the given +@var{locspec} resolves to. @var{locspec} can specify a function name, +a line number, an address of an instruction, and more. @xref{Location +Specifications}, for the various forms of @var{locspec}. The +breakpoint will stop your program just before it executes the +instruction at the address of any of the breakpoint's locations. -When using source languages that permit overloading of symbols, such as -C@t{++}, a function name may refer to more than one possible place to break. -@xref{Ambiguous Expressions,,Ambiguous Expressions}, for a discussion of -that situation. +When using source languages that permit overloading of symbols, such +as C@t{++}, a function name may refer to more than one symbol, and +thus more than one place to break. @xref{Ambiguous +Expressions,,Ambiguous Expressions}, for a discussion of that +situation. It is also possible to insert a breakpoint that will stop the program only if a specific thread (@pxref{Thread-Specific Breakpoints}) @@ -4614,35 +4616,16 @@ the breakpoints are conditional, this is even useful @cindex multiple locations, breakpoints @cindex breakpoints, multiple locations -It is possible that a breakpoint corresponds to several locations -in your program. Examples of this situation are: - -@itemize @bullet -@item -Multiple functions in the program may have the same name. - -@item -For a C@t{++} constructor, the @value{NGCC} compiler generates several -instances of the function body, used in different cases. - -@item -For a C@t{++} template function, a given line in the function can -correspond to any number of instantiations. - -@item -For an inlined function, a given source line can correspond to -several places where that function is inlined. -@end itemize - -In all those cases, @value{GDBN} will insert a breakpoint at all -the relevant locations. +It is possible that a single logical breakpoint is set at several code +locations in your program. @xref{Location Specifications}, for +examples. A breakpoint with multiple locations is displayed in the breakpoint table using several rows---one header row, followed by one row for each breakpoint location. The header row has @samp{} in the -address column. The rows for individual locations contain the actual -addresses for locations, and show the functions to which those -locations belong. The number column for a location is of the form +address column. Each breakpoint location row contains the actual +address, source file, source line and function of its code location. +The number column for a breakpoint location is of the form @var{breakpoint-number}.@var{location-number}. For example: @@ -4711,31 +4694,34 @@ differ from regular breakpoints. You can set conditions or commands, enable and disable them and perform other breakpoint operations. @value{GDBN} provides some additional commands for controlling what -happens when the @samp{break} command cannot resolve breakpoint -address specification to an address: +happens when the @samp{break} command cannot resolve the location spec +to any code location in your program (@pxref{Location +Specifications}): @kindex set breakpoint pending @kindex show breakpoint pending @table @code @item set breakpoint pending auto -This is the default behavior. When @value{GDBN} cannot find the breakpoint -location, it queries you whether a pending breakpoint should be created. +This is the default behavior. When @value{GDBN} cannot resolve the +location spec, it should create a pending breakpoint without +confirmation. @item set breakpoint pending on -This indicates that an unrecognized breakpoint location should automatically -result in a pending breakpoint being created. +This indicates that when @value{GDBN} cannot resolve the location +spec, it should create a pending breakpoint without confirmation. @item set breakpoint pending off -This indicates that pending breakpoints are not to be created. Any -unrecognized breakpoint location results in an error. This setting does -not affect any pending breakpoints previously created. +This indicates that pending breakpoints are not to be created. If +@value{GDBN} cannot resolve the location spec, it aborts the +breakpoint creation with an error. This setting does not affect any +pending breakpoints previously created. @item show breakpoint pending Show the current behavior setting for creating pending breakpoints. @end table The settings above only affect the @code{break} command and its -variants. Once breakpoint is set, it will be automatically updated +variants. Once a breakpoint is set, it will be automatically updated as shared libraries are loaded and unloaded. @cindex automatic hardware breakpoints @@ -5455,10 +5441,10 @@ selected stack frame (@pxref{Selection, ,Selecting a Frame}). When the innermost frame is selected, this is a good way to delete a breakpoint where your program just stopped. -@item clear @var{location} -Delete any breakpoints set at the specified @var{location}. -@xref{Specify Location}, for the various forms of @var{location}; the -most useful ones are listed below: +@item clear @var{locspec} +Delete breakpoints with code locations that match @var{locspec}. +@xref{Location Specifications}, for the various forms of +@var{locspec}; the most useful ones are listed below: @table @code @item clear @var{function} @@ -5815,10 +5801,11 @@ everything without needing to communicate with @value{GDBN}. @table @code @kindex dprintf -@item dprintf @var{location},@var{template},@var{expression}[,@var{expression}@dots{}] -Whenever execution reaches @var{location}, print the values of one or -more @var{expressions} under the control of the string @var{template}. -To print several values, separate them with commas. +@item dprintf @var{locspec},@var{template},@var{expression}[,@var{expression}@dots{}] +Whenever execution reaches a code location in your program that +matches @var{locspec}, print the values of one or more +@var{expressions} under the control of the string @var{template}. To +print several values, separate them with commas. @item set dprintf-style @var{style} Set the dprintf output to be handled in one of several different @@ -6313,11 +6300,13 @@ statement---not in terms of the actual machine code. instruction stepping, and hence is slower than @code{until} with an argument. -@item until @var{location} -@itemx u @var{location} -Continue running your program until either the specified @var{location} is -reached, or the current stack frame returns. The location is any of -the forms described in @ref{Specify Location}. +@item until @var{locspec} +@itemx u @var{locspec} +Continue running your program until either a code location in your +program that matches @var{locspec} is reached, or the current stack +frame returns. +@var{locspec} is any of the forms described in @ref{Location +Specifications}. This form of the command uses temporary breakpoints, and hence is quicker than @code{until} without an argument. The specified location is actually reached only if it is in the current frame. This @@ -6338,11 +6327,11 @@ invocations have returned. @end smallexample -@kindex advance @var{location} -@item advance @var{location} -Continue running the program up to the given @var{location}. An argument is -required, which should be of one of the forms described in -@ref{Specify Location}. +@kindex advance @var{locspec} +@item advance @var{locspec} +Continue running the program up to the code location indicated by +@var{locspec}. An argument is required, which should be of one of the +forms described in @ref{Location Specifications}. Execution will also stop upon exit from the current stack frame. This command is similar to @code{until}, but @code{advance} will not skip over recursive function calls, and the target location doesn't @@ -6442,7 +6431,7 @@ A more flexible solution is to execute @kbd{skip boring}. This instructs @code{foo}. Functions may be skipped by providing either a function name, linespec -(@pxref{Specify Location}), regular expression that matches the function's +(@pxref{Location Specifications}), regular expression that matches the function's name, file name or a @code{glob}-style pattern that matches the file name. On Posix systems the form of the regular expression is @@ -6479,7 +6468,7 @@ over when stepping. @itemx -fu @var{linespec} Functions named by @var{linespec} or the function containing the line named by @var{linespec} will be skipped over when stepping. -@xref{Specify Location}. +@xref{Location Specifications}. @item -rfunction @var{regexp} @itemx -rfu @var{regexp} @@ -6512,7 +6501,7 @@ will be skipped. @item skip function @r{[}@var{linespec}@r{]} After running this command, the function named by @var{linespec} or the function containing the line named by @var{linespec} will be skipped over when -stepping. @xref{Specify Location}. +stepping. @xref{Location Specifications}. If you do not specify @var{linespec}, the function you're currently debugging will be skipped. @@ -7141,11 +7130,10 @@ breakpoints on all threads, or on a particular thread. @cindex breakpoints and threads @cindex thread breakpoints @kindex break @dots{} thread @var{thread-id} -@item break @var{location} thread @var{thread-id} -@itemx break @var{location} thread @var{thread-id} if @dots{} -@var{location} specifies source lines; there are several ways of -writing them (@pxref{Specify Location}), but the effect is always to -specify some source line. +@item break @var{locspec} thread @var{thread-id} +@itemx break @var{locspec} thread @var{thread-id} if @dots{} +@var{locspec} specifies a code location or locations in your program. +@xref{Location Specifications}, for details. Use the qualifier @samp{thread @var{thread-id}} with a breakpoint command to specify that you only want @value{GDBN} to stop the program when a @@ -8945,7 +8933,7 @@ prefer to use Emacs facilities to view source; see @ref{Emacs, ,Using @menu * List:: Printing source lines -* Specify Location:: How to specify code locations +* Location Specifications:: How to specify code locations * Edit:: Editing source files * Search:: Searching source files * Source Path:: Specifying source directories @@ -8961,7 +8949,7 @@ prefer to use Emacs facilities to view source; see @ref{Emacs, ,Using To print lines from a source file, use the @code{list} command (abbreviated @code{l}). By default, ten lines are printed. There are several ways to specify what part of the file you want to -print; see @ref{Specify Location}, for the full list. +print; see @ref{Location Specifications}, for the full list. Here are the forms of the @code{list} command most commonly used: @@ -9008,26 +8996,35 @@ than listing the same lines again. An exception is made for an argument of @samp{-}; that argument is preserved in repetition so that each repetition moves up in the source file. -In general, the @code{list} command expects you to supply zero, one or two -@dfn{locations}. Locations specify source lines; there are several ways -of writing them (@pxref{Specify Location}), but the effect is always -to specify some source line. +In general, the @code{list} command expects you to supply zero, one or +two location specs. These location specs are interpreted to specify +source code lines; there are several ways of writing them +(@pxref{Location Specifications}), but the effect is always to specify +some source lines to display. Here is a complete description of the possible arguments for @code{list}: @table @code -@item list @var{location} -Print lines centered around the line specified by @var{location}. +@item list @var{locspec} +Print lines centered around the line or lines that @var{locspec} +resolves to. @item list @var{first},@var{last} Print lines from @var{first} to @var{last}. Both arguments are -locations. When a @code{list} command has two locations, and the -source file of the second location is omitted, this refers to -the same source file as the first location. +location specs. When a @code{list} command has two location specs, +and the source file of the second location spec is omitted, this +refers to the same source file as the first location spec. If either +@var{first} or @var{last} resolve to more than one source line in the +program, then the list command will show the list of resolved source +lines and does not proceed with the source code listing. @item list ,@var{last} Print lines ending with @var{last}. +Likewise, if @var{last} resolves to more than one source line in the +program, then the list command will print the list of resolved source +lines and does not proceed with the source code listing. + @item list @var{first}, Print lines starting with @var{first}. @@ -9041,17 +9038,75 @@ Print lines just before the lines last printed. As described in the preceding table. @end table -@node Specify Location -@section Specifying a Location +@node Location Specifications +@section Location Specifications @cindex specifying location -@cindex location +@cindex location spec +@cindex locspec @cindex source location +@cindex code location Several @value{GDBN} commands accept arguments that specify a location -of your program's code. Since @value{GDBN} is a source-level -debugger, a location usually specifies some line in the source code. -Locations may be specified using three different formats: -linespec locations, explicit locations, or address locations. +or locations of your program's code. Since @value{GDBN} is a +source-level debugger, a location specification usually indicates some +line in the source code, but it can also indicate a function name, an +address, a label, and more. + +A concrete code location in your program is uniquely identifiable by a +set of logical attributes. Typically, a line number, the source file +the line belongs to, the fully-qualified and prototyped function it is +defined in, and an instruction address. Because each inferior has its +own address space, also an inferior number. + +On the other hand, a @dfn{location specification} (a.k.a.@: location +spec) is a way to find or refer to the concrete code locations in the +program. A location spec serves as a blueprint, and @value{GDBN} +resolves the spec to actual code locations in your program by using +the source and debug information. + +The location spec may be incomplete, and @value{GDBN} will do its best +to find all the locations in the program that match it. For example, +a location spec may just indicate a line number and a source filename +with no directory components, or even not specify a filename at all, +just a line number. Or, the spec may indicate a simple function name +instead of a fully-qualified and prototyped function name (e.g., +@code{func} instead of @code{A::func(int)}). + +You may not have debug info for some of the instructions in the +program, so a resolved location that itself points to such code will +be incomplete and be missing some attributes, such as the source file +and line number, and sometimes even function names. Such an +incomplete location is only usable in contexts that work with +addresses and/or function names. Some commands can only work with +complete locations. + +Here are examples of typical situations that result in a location spec +matching multiple concrete code locations in your program: + +@itemize @bullet +@item +The location spec specifies a function name, and multiple functions in +the program may have the same name. + +@item +The location spec specifies a file name, and multiple files in the +program share the same name. + +@item +For a C@t{++} constructor, the @value{NGCC} compiler generates several +instances of the function body, used in different cases. + +@item +For a C@t{++} template function, a given line in the function can +correspond to any number of instantiations. + +@item +For an inlined function, a given source line can correspond to several +places where that function is inlined. +@end itemize + +Locations may be specified using three different formats: linespec +locations, explicit locations, or address locations. @menu * Linespec Locations:: Linespec locations @@ -9270,12 +9325,17 @@ Alternatively, there are several ways to specify what part of the file you want to print if you want to see other parts of the program: @table @code -@item edit @var{location} -Edit the source file specified by @code{location}. Editing starts at -that @var{location}, e.g., at the specified source line of the -specified file. @xref{Specify Location}, for all the possible forms -of the @var{location} argument; here are the forms of the @code{edit} -command most commonly used: +@item edit @var{locspec} +Edit the source file specified by @code{locspec}. Editing starts at +the source file and source line @code{locspec} resolves to. +@xref{Location Specifications}, for all the possible forms of the +@var{locspec} argument. + +If @code{locspec} resolves to more than one source line in your +program, then the command prints the list of resolved source lines and +does not proceed with the editing. + +Here are the forms of the @code{edit} command most commonly used: @table @code @item edit @var{number} @@ -9655,11 +9715,12 @@ well as hex. @table @code @kindex info line @item info line -@itemx info line @var{location} +@itemx info line @var{locspec} Print the starting and ending addresses of the compiled code for -source line @var{location}. You can specify source lines in any of -the ways documented in @ref{Specify Location}. With no @var{location} -information about the current source line is printed. +source lines that @var{locspec} resolves to. @xref{Location +Specifications}, for the various forms of @var{locspec}. +With no @var{locspec}, information about the current source line is +printed. @end table For example, we can use @code{info line} to discover the location of @@ -9674,8 +9735,9 @@ Line 895 of "builtin.c" starts at pc 0x634c and \ @noindent @cindex code address and its source line -We can also inquire (using @code{*@var{addr}} as the form for -@var{location}) what source line covers a particular address: +We can also inquire, using @code{*@var{addr}} as the form for +@var{locspec}, what source line covers a particular address +@var{addr}: @smallexample (@value{GDBP}) info line *0x63ff Line 926 of "builtin.c" starts at pc 0x63e4 and \ @@ -9883,10 +9945,10 @@ Dump of assembler code from 0x400281 to 0x40028b: End of assembler dump. @end smallexample -Addresses cannot be specified as a location (@pxref{Specify Location}). -So, for example, if you want to disassemble function @code{bar} -in file @file{foo.c}, you must type @samp{disassemble 'foo.c'::bar} -and not @samp{disassemble foo.c:bar}. +Addresses cannot be specified with a location spec (@pxref{Location +Specifications}). So, for example, if you want to disassemble +function @code{bar} in file @file{foo.c}, you must type +@samp{disassemble 'foo.c'::bar} and not @samp{disassemble foo.c:bar}. Some architectures have more than one commonly-used set of instruction mnemonics or other syntax. @@ -14172,10 +14234,10 @@ argument processing and the beginning of @var{macro} for non C-like macros where the macro may begin with a hyphen. @kindex info macros -@item info macros @var{location} -Show all macro definitions that are in effect at the location specified -by @var{location}, and describe the source location or compiler -command-line where those definitions were established. +@item info macros @var{locspec} +Show all macro definitions that are in effect at the source line +@var{locspec} resolves to, and describe the source location +or compiler command-line where those definitions were established. @kindex macro define @cindex user-defined macros @@ -14477,10 +14539,10 @@ conditions and actions. @table @code @cindex set tracepoint @kindex trace -@item trace @var{location} +@item trace @var{locspec} The @code{trace} command is very similar to the @code{break} command. -Its argument @var{location} can be any valid location. -@xref{Specify Location}. The @code{trace} command defines a tracepoint, +Its argument @var{locspec} can be any valid location specification. +@xref{Location Specifications}. The @code{trace} command defines a tracepoint, which is a point in the target program where the debugger will briefly stop, collect some data, and then allow the program to continue. Setting a tracepoint or changing its actions takes effect immediately if the remote stub @@ -14516,14 +14578,14 @@ Here are some examples of using the @code{trace} command: @noindent You can abbreviate @code{trace} as @code{tr}. -@item trace @var{location} if @var{cond} +@item trace @var{locspec} if @var{cond} Set a tracepoint with condition @var{cond}; evaluate the expression @var{cond} each time the tracepoint is reached, and collect data only if the value is nonzero---that is, if @var{cond} evaluates as true. @xref{Tracepoint Conditions, ,Tracepoint Conditions}, for more information on tracepoint conditions. -@item ftrace @var{location} [ if @var{cond} ] +@item ftrace @var{locspec} [ if @var{cond} ] @cindex set fast tracepoint @cindex fast tracepoints, setting @kindex ftrace @@ -14555,20 +14617,21 @@ sudo sysctl -w vm.mmap_min_addr=32768 which sets the low address to 32K, which leaves plenty of room for trampolines. The minimum address should be set to a page boundary. -@item strace @var{location} [ if @var{cond} ] +@item strace [@var{locspec} | -m @var{marker}] [ if @var{cond} ] @cindex set static tracepoint @cindex static tracepoints, setting @cindex probe static tracepoint marker @kindex strace The @code{strace} command sets a static tracepoint. For targets that support it, setting a static tracepoint probes a static -instrumentation point, or marker, found at @var{location}. It may not -be possible to set a static tracepoint at the desired location, in -which case the command will exit with an explanatory message. +instrumentation point, or marker, found at the code locations that match +@var{locspec}. It may not be possible to set a static tracepoint at +the desired location, in which case the command will exit with an +explanatory message. @value{GDBN} handles arguments to @code{strace} exactly as for @code{trace}, with the addition that the user can also specify -@code{-m @var{marker}} as @var{location}. This probes the marker +@code{-m @var{marker}} instead of a location spec. This probes the marker identified by the @var{marker} string identifier. This identifier depends on the static tracepoint backend library your program is using. You can find all the marker identifiers in the @samp{ID} field @@ -17439,9 +17502,9 @@ peculiarities and holes to be aware of. @itemize @bullet @item -Linespecs (@pxref{Specify Location}) are never relative to the current -crate. Instead, they act as if there were a global namespace of -crates, somewhat similar to the way @code{extern crate} behaves. +Linespecs (@pxref{Location Specifications}) are never relative to the +current crate. Instead, they act as if there were a global namespace +of crates, somewhat similar to the way @code{extern crate} behaves. That is, if @value{GDBN} is stopped at a breakpoint in a function in crate @samp{A}, module @samp{B}, then @code{break B::f} will attempt @@ -18762,15 +18825,14 @@ information. Flags @code{-c} and @code{-s} cannot be used together. -@item break @var{location} task @var{taskno} -@itemx break @var{location} task @var{taskno} if @dots{} +@item break @var{locspec} task @var{taskno} +@itemx break @var{locspec} task @var{taskno} if @dots{} @cindex breakpoints and tasks, in Ada @cindex task breakpoints, in Ada @kindex break @dots{} task @var{taskno}@r{ (Ada)} These commands are like the @code{break @dots{} thread @dots{}} -command (@pxref{Thread Stops}). The -@var{location} argument specifies source lines, as described -in @ref{Specify Location}. +command (@pxref{Thread Stops}). @xref{Location Specifications}, for +the various forms of @var{locspec}. Use the qualifier @samp{task @var{taskno}} with a breakpoint command to specify that you only want @value{GDBN} to stop the program when a @@ -19531,12 +19593,10 @@ These commands can be used to enable or disable type printers. @kindex info scope @cindex local variables -@item info scope @var{location} -List all the variables local to a particular scope. This command -accepts a @var{location} argument---a function name, a source line, or -an address preceded by a @samp{*}, and prints all the variables local -to the scope defined by that location. (@xref{Specify Location}, for -details about supported forms of @var{location}.) For example: +@item info scope @var{locspec} +List all the variables local to the lexical scope @var{locspec} +resolves to. @xref{Location Specifications}, for details about +supported forms of @var{locspec}. For example: @smallexample (@value{GDBP}) @b{info scope command_line_handler} @@ -20124,23 +20184,26 @@ an address of your own choosing, with the following commands: @table @code @kindex jump @kindex j @r{(@code{jump})} -@item jump @var{location} -@itemx j @var{location} -Resume execution at @var{location}. Execution stops again immediately -if there is a breakpoint there. @xref{Specify Location}, for a description -of the different forms of @var{location}. It is common -practice to use the @code{tbreak} command in conjunction with -@code{jump}. @xref{Set Breaks, ,Setting Breakpoints}. +@item jump @var{locspec} +@itemx j @var{locspec} +Resume execution at the address @var{locspec} resolves to. +@xref{Location Specifications}, for a description of the different +forms of @var{locspec}. If @var{locspec} resolves to more than one +address, the command aborts before jumping. +Execution stops again immediately if there is a breakpoint there. It +is common practice to use the @code{tbreak} command in conjunction +with @code{jump}. @xref{Set Breaks, ,Setting Breakpoints}. The @code{jump} command does not change the current stack frame, or the stack pointer, or the contents of any memory location or any -register other than the program counter. If @var{location} is in -a different function from the one currently executing, the results may -be bizarre if the two functions expect different patterns of arguments or -of local variables. For this reason, the @code{jump} command requests -confirmation if the specified line is not in the function currently -executing. However, even bizarre results are predictable if you are -well acquainted with the machine-language code of your program. +register other than the program counter. If @var{locspec} resolves to +an address in a different function from the one currently executing, the +results may be bizarre if the two functions expect different patterns +of arguments or of local variables. For this reason, the @code{jump} +command requests confirmation if the specified line is not in the +function currently executing. However, even bizarre results are +predictable if you are well acquainted with the machine-language code +of your program. @end table On many systems, you can get much the same effect as the @code{jump} @@ -25365,15 +25428,16 @@ use the @code{break-range} command. @table @code @kindex break-range -@item break-range @var{start-location}, @var{end-location} -Set a breakpoint for an address range given by -@var{start-location} and @var{end-location}, which can specify a function name, -a line number, an offset of lines from the current line or from the start -location, or an address of an instruction (see @ref{Specify Location}, -for a list of all the possible ways to specify a @var{location}.) -The breakpoint will stop execution of the inferior whenever it -executes an instruction at any address within the specified range, -(including @var{start-location} and @var{end-location}.) +@item break-range @var{start-locspec}, @var{end-locspec} +Set a breakpoint for an address range given by @var{start-locspec} and +@var{end-locspec}, which are location specs. @xref{Location +Specifications}, for a list of all the possible forms of location +specs. If either @var{start-locspec} or @var{end-locspec} resolve to +multiple addresses in the program, then the command aborts with an +error without creating a breakpoint. The breakpoint will stop +execution of the inferior whenever it executes an instruction at any +address within the specified range, including @var{start-locspec} and +@var{end-locspec}. @kindex set powerpc @item set powerpc soft-float @@ -31192,11 +31256,11 @@ N.A. @smallexample -break-insert [ -t ] [ -h ] [ -f ] [ -d ] [ -a ] [ --qualified ] [ -c @var{condition} ] [ --force-condition ] [ -i @var{ignore-count} ] - [ -p @var{thread-id} ] [ @var{location} ] + [ -p @var{thread-id} ] [ @var{locspec} ] @end smallexample @noindent -If specified, @var{location}, can be one of: +If specified, @var{locspec}, can be one of: @table @var @item linespec location @@ -31235,10 +31299,10 @@ Insert a temporary breakpoint. @item -h Insert a hardware breakpoint. @item -f -If @var{location} cannot be parsed (for example if it +If @var{locspec} cannot be parsed (for example if it refers to unknown files or functions), create a pending breakpoint. Without this flag, @value{GDBN} will report -an error, and won't create a breakpoint, if @var{location} +an error, and won't create a breakpoint, if @var{locspec} cannot be parsed. @item -d Create a disabled breakpoint. @@ -31320,12 +31384,12 @@ times="0"@}]@} @smallexample -dprintf-insert [ -t ] [ -f ] [ -d ] [ --qualified ] [ -c @var{condition} ] [--force-condition] [ -i @var{ignore-count} ] - [ -p @var{thread-id} ] [ @var{location} ] [ @var{format} ] + [ -p @var{thread-id} ] [ @var{locspec} ] [ @var{format} ] [ @var{argument} ] @end smallexample @noindent -If supplied, @var{location} and @code{--qualified} may be specified +If supplied, @var{locspec} and @code{--qualified} may be specified the same way as for the @code{-break-insert} command. @xref{-break-insert}. @@ -31335,10 +31399,10 @@ The possible optional parameters of this command are: @item -t Insert a temporary breakpoint. @item -f -If @var{location} cannot be parsed (for example, if it +If @var{locspec} cannot be parsed (for example, if it refers to unknown files or functions), create a pending breakpoint. Without this flag, @value{GDBN} will report -an error, and won't create a breakpoint, if @var{location} +an error, and won't create a breakpoint, if @var{locspec} cannot be parsed. @item -d Create a disabled breakpoint. @@ -32551,12 +32615,12 @@ fullname="/home/foo/bar/try.c",line="13",arch="i386:x86_64"@} @subsubheading Synopsis @smallexample - -exec-jump @var{location} + -exec-jump @var{locspec} @end smallexample Resumes execution of the inferior program at the location specified by -parameter. @xref{Specify Location}, for a description of the -different forms of @var{location}. +the parameter. @xref{Location Specifications}, for a description of +the different forms of @var{locspec}. @subsubheading @value{GDBN} Command @@ -32870,13 +32934,13 @@ fullname="/home/foo/bar/try.c",line="10",arch="i386:x86_64"@} @subsubheading Synopsis @smallexample - -exec-until [ @var{location} ] + -exec-until [ @var{locspec} ] @end smallexample -Executes the inferior until the @var{location} specified in the -argument is reached. If there is no argument, the inferior executes -until a source line greater than the current one is reached. The -reason for stopping in this case will be @samp{location-reached}. +Executes the inferior until the address @var{locspec} resolves to. If +there is no argument, the inferior executes until a source line +greater than the current one is reached. The reason for stopping in +this case will be @samp{location-reached}. @subsubheading @value{GDBN} Command @@ -34935,7 +34999,7 @@ next trace frame that corresponds to a tracepoint at an address outside the specified range. Both bounds are considered to be inside the range. @item line -Line specification is required as parameter. @xref{Specify Location}. +Location specification is required as parameter. @xref{Location Specifications}. Finds next trace frame that corresponds to a tracepoint at the specified location. @@ -39438,8 +39502,8 @@ messages, see @ref{Debugging Output}.) @table @code @kindex maint agent @kindex maint agent-eval -@item maint agent @r{[}-at @var{location}@r{,}@r{]} @var{expression} -@itemx maint agent-eval @r{[}-at @var{location}@r{,}@r{]} @var{expression} +@item maint agent @r{[}-at @var{linespec}@r{,}@r{]} @var{expression} +@itemx maint agent-eval @r{[}-at @var{linespec}@r{,}@r{]} @var{expression} Translate the given @var{expression} into remote agent bytecodes. This command is useful for debugging the Agent Expression mechanism (@pxref{Agent Expressions}). The @samp{agent} version produces an @@ -39450,7 +39514,8 @@ globb} will include bytecodes to record four bytes of memory at each of the addresses of @code{globa} and @code{globb}, while discarding the result of the addition, while an evaluation expression will do the addition and return the sum. -If @code{-at} is given, generate remote agent bytecode for @var{location}. +If @code{-at} is given, generate remote agent bytecode for all +the addresses @var{linespec} resolves to (@pxref{Linespec Locations}). If not, generate remote agent bytecode for current frame PC address. @kindex maint agent-printf diff --git a/gdb/doc/guile.texi b/gdb/doc/guile.texi index 3c517230929..63916eed181 100644 --- a/gdb/doc/guile.texi +++ b/gdb/doc/guile.texi @@ -1965,7 +1965,7 @@ This constant means that filename completion should be performed. @item COMPLETE_LOCATION This constant means that location completion should be done. -@xref{Specify Location}. +@xref{Location Specifications}. @item COMPLETE_COMMAND This constant means that completion should examine @value{GDBN} diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi index cb5283e03c0..f933c7d30c9 100644 --- a/gdb/doc/python.texi +++ b/gdb/doc/python.texi @@ -577,7 +577,8 @@ either @code{None} or another tuple that contains all the locations that match the expression represented as @code{gdb.Symtab_and_line} objects (@pxref{Symbol Tables In Python}). If @var{expression} is provided, it is decoded the way that @value{GDBN}'s inbuilt -@code{break} or @code{edit} commands do (@pxref{Specify Location}). +@code{break} or @code{edit} commands do (@pxref{Location +Specifications}). @end defun @defun gdb.prompt_hook (current_prompt) @@ -4186,7 +4187,7 @@ This constant means that filename completion should be performed. @vindex COMPLETE_LOCATION @item gdb.COMPLETE_LOCATION This constant means that location completion should be done. -@xref{Specify Location}. +@xref{Location Specifications}. @vindex COMPLETE_COMMAND @item gdb.COMPLETE_COMMAND base-commit: fbcda577011d73fdcf1ebf86160b6fc8ddd95299 -- 2.36.0