diff mbox

GDB version as convenience variable

Message ID 83r2aun9mk.fsf@gnu.org
State New
Headers show

Commit Message

Eli Zaretskii March 25, 2019, 5:31 p.m. UTC
Seems like there's a consensus to have 2 separate variables, so here's
a version of the patch that does that.  OK to commit?

Comments

Simon Marchi March 25, 2019, 5:58 p.m. UTC | #1
On 2019-03-25 1:31 p.m., Eli Zaretskii wrote:
> --- a/gdb/doc/gdb.texinfo
> +++ b/gdb/doc/gdb.texinfo
> @@ -11211,6 +11211,17 @@
>   @item $_gthread
>   The global number of the current thread.  @xref{global thread numbers}.
>   
> +@item $_gdb_major
> +@itemx $_gdb_minor
> +@vindex $_gdb_major@{, convenience variable}
> +@vindex $_gdb_minor@{, convenience variable}
> +The major and minor version numbers of the running @value{GDBN}.
> +Development snapshots and pretest versions have their minor version
> +incremented by one; thus, @value{GDBN} pretest 9.11.90 will produce
> +the value 12 for @code{$_gdb_minor}.  These variables allow you to
> +write scripts that work with different versions of @value{GDBN}
> +without errors caused by features unavailable in some of those
> +versions.
>   @end table

I get this error when trying to "make html":

/home/smarchi/src/binutils-gdb/gdb/doc/gdb.texinfo:11216: misplaced }
/home/smarchi/src/binutils-gdb/gdb/doc/gdb.texinfo:11217: misplaced }

Is it worth having a test for that?  If we check that they have the 
expected value, it would be something to change when a new GDB branch is 
created, probably (as the master branch will now represent the next 
version).  Maybe our release manager should have a say in this :).

Otherwise, this LGTM.

Simon
Eli Zaretskii March 25, 2019, 6:10 p.m. UTC | #2
> From: Simon Marchi <simark@simark.ca>
> Date: Mon, 25 Mar 2019 13:58:20 -0400
> 
> > +@item $_gdb_major
> > +@itemx $_gdb_minor
> > +@vindex $_gdb_major@{, convenience variable}
> > +@vindex $_gdb_minor@{, convenience variable}
> > +The major and minor version numbers of the running @value{GDBN}.
> > +Development snapshots and pretest versions have their minor version
> > +incremented by one; thus, @value{GDBN} pretest 9.11.90 will produce
> > +the value 12 for @code{$_gdb_minor}.  These variables allow you to
> > +write scripts that work with different versions of @value{GDBN}
> > +without errors caused by features unavailable in some of those
> > +versions.
> >   @end table
> 
> I get this error when trying to "make html":
> 
> /home/smarchi/src/binutils-gdb/gdb/doc/gdb.texinfo:11216: misplaced }
> /home/smarchi/src/binutils-gdb/gdb/doc/gdb.texinfo:11217: misplaced }

Thanks, fixed.  Too many r's...

> Is it worth having a test for that?

Hmm... how would you test that?

> If we check that they have the expected value, it would be something
> to change when a new GDB branch is created, probably (as the master
> branch will now represent the next version).  Maybe our release
> manager should have a say in this :).

I'm all ears.

> Otherwise, this LGTM.

Thanks for the review.
Simon Marchi March 25, 2019, 6:33 p.m. UTC | #3
On 2019-03-25 14:10, Eli Zaretskii wrote:
>> Is it worth having a test for that?
> 
> Hmm... how would you test that?

Something like

gdb_test "print \$_gdb_major" " = 8"
gdb_test "print \$_gdb_minor" " = 4"

Simon
Simon Marchi March 25, 2019, 6:37 p.m. UTC | #4
On 2019-03-25 14:33, Simon Marchi wrote:
> On 2019-03-25 14:10, Eli Zaretskii wrote:
>>> Is it worth having a test for that?
>> 
>> Hmm... how would you test that?
> 
> Something like
> 
> gdb_test "print \$_gdb_major" " = 8"
> gdb_test "print \$_gdb_minor" " = 4"
> 
> Simon

Or, the test could somehow automatically get the current version of GDB 
and compare $_gdb_major/$_gdb_minor against that, so that we don't need 
to modify it at every release.

Simon
Eli Zaretskii March 25, 2019, 6:43 p.m. UTC | #5
> Date: Mon, 25 Mar 2019 14:33:55 -0400
> From: Simon Marchi <simark@simark.ca>
> Cc: gdb-patches@sourceware.org, brobecker@adacore.com
> 
> > Hmm... how would you test that?
> 
> Something like
> 
> gdb_test "print \$_gdb_major" " = 8"
> gdb_test "print \$_gdb_minor" " = 4"

This would require changes with each new version.  I thought you had
in mind comparison with output of "gdb --version", suitably edited.
Simon Marchi March 25, 2019, 6:51 p.m. UTC | #6
On 2019-03-25 14:43, Eli Zaretskii wrote:
>> Date: Mon, 25 Mar 2019 14:33:55 -0400
>> From: Simon Marchi <simark@simark.ca>
>> Cc: gdb-patches@sourceware.org, brobecker@adacore.com
>> 
>> > Hmm... how would you test that?
>> 
>> Something like
>> 
>> gdb_test "print \$_gdb_major" " = 8"
>> gdb_test "print \$_gdb_minor" " = 4"
> 
> This would require changes with each new version.  I thought you had
> in mind comparison with output of "gdb --version", suitably edited.

Yes, that's why I wondered initially if it was worth adding a test like 
this, since it would impose an additional burden on the person doing the 
release.  However, comparing the output with gdb --version, or some 
other automated mean, would be perfect.

Simon
Eli Zaretskii March 25, 2019, 7:18 p.m. UTC | #7
> Date: Mon, 25 Mar 2019 14:51:36 -0400
> From: Simon Marchi <simark@simark.ca>
> Cc: gdb-patches@sourceware.org, brobecker@adacore.com
> 
> comparing the output with gdb --version, or some other automated
> mean, would be perfect.

Well, I never wrote any tests for GDB, and I'm not sure I have a
system on which to run such a test.  So I hope someone else will add
this test.
diff mbox

Patch

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2de1adc..f841e0a 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@ 
+2019-03-06  Eli Zaretskii  <eliz@gnu.org>
+
+	* NEWS: Announce $_gdb_major and $_gdb_minor.
+
+	* top.c (init_gdb_version_vars): New function.
+	(gdb_init): Call init_gdb_version_vars.
+
 2019-03-25  Alan Hayward  <alan.hayward@arm.com>
 
 	* s390-linux-nat.c: Add include.
diff --git a/gdb/NEWS b/gdb/NEWS
index c45b313..676f0a0 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,12 @@ 
 
 *** Changes since GDB 8.3
 
+* New built-in convenience variables $_gdb_major and $_gdb_minor
+  provide the GDB version.  They are handy for conditionally using
+  features available only in or since specific GDB versions, in
+  scripts that should work error-free with many different versions,
+  such as in system-wide init files.
+
 *** Changes in GDB 8.3
 
 * GDB and GDBserver now support access to additional registers on
diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index 1f41498..c384267 100644
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,3 +1,7 @@ 
+2019-03-06  Eli Zaretskii  <eliz@gnu.org>
+
+	* gdb.texinfo (Convenience Vars): Document $_gdb_version.
+
 2019-03-22  Alan Hayward  <alan.hayward@arm.com>
 	    Jiong Wang  <jiong.wang@arm.com>
 
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 4c1d5e8..115bcf7 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -11211,6 +11211,17 @@ 
 @item $_gthread
 The global number of the current thread.  @xref{global thread numbers}.
 
+@item $_gdb_major
+@itemx $_gdb_minor
+@vindex $_gdb_major@{, convenience variable}
+@vindex $_gdb_minor@{, convenience variable}
+The major and minor version numbers of the running @value{GDBN}.
+Development snapshots and pretest versions have their minor version
+incremented by one; thus, @value{GDBN} pretest 9.11.90 will produce
+the value 12 for @code{$_gdb_minor}.  These variables allow you to
+write scripts that work with different versions of @value{GDBN}
+without errors caused by features unavailable in some of those
+versions.
 @end table
 
 @node Convenience Funs
diff --git a/gdb/top.c b/gdb/top.c
index b10b064..afb77c0 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -2003,6 +2004,17 @@  set_history_filename (const char *args,
 }
 
 static void
+init_gdb_version_vars (void)
+{
+  struct internalvar *major_version_var = create_internalvar ("_gdb_major");
+  struct internalvar *minor_version_var = create_internalvar ("_gdb_minor");
+  int vmajor = 0, vminor = 0, vrevision = 0;
+  sscanf (version, "%d.%d.%d", &vmajor, &vminor, &vrevision);
+  set_internalvar_integer (major_version_var, vmajor);
+  set_internalvar_integer (minor_version_var, vminor + (vrevision > 0));
+}
+
+static void
 init_main (void)
 {
   struct cmd_list_element *c;
@@ -2206,4 +2218,7 @@  gdb_init (char *argv0)
      prefix to be installed.  Keep things simple and just do final
      script initialization here.  */
   finish_ext_lang_initialization ();
+
+  /* Create $_gdb_major and $_gdb_minor convenience variables.  */
+  init_gdb_version_vars ();
 }