[PATCH v2] Use "output-radix" setting to format function offsets

[Zander Work <zdw@google.com>]

Updates since v1:

* Addressed feedback in the test suite by more robustly handling the
  GDB I/O and improved the regex patterns used to match on the offset
  values.
* Updated the accompanying test program to have a minimum level of
  complexity to avoid compiler optimizations trimming out too much
  function body, and fixed the formatting and copyright date
* Added a comment on the `format_pc_offset()` implementation and
  addressed comments in that function.

I believe the only open items are:

* Should MI consumers have the string radix-formatted offset value, or
  continue having an int value (this is the current impl in the patch)?
* I still need to do an FSF copyright assignment.

Please let me know if I missed anything else to address. Thanks!
---
 gdb/disasm.c                     | 18 ++++++++++---
 gdb/printcmd.c                   |  2 +-
 gdb/testsuite/gdb.base/radix.c   | 35 ++++++++++++++++++++++++++
 gdb/testsuite/gdb.base/radix.exp | 43 ++++++++++++++++++++++++++++++++
 gdb/valprint.c                   | 13 ++++++++++
 gdb/valprint.h                   |  6 +++++
 6 files changed, 112 insertions(+), 5 deletions(-)
 create mode 100644 gdb/testsuite/gdb.base/radix.c

diff --git a/gdb/disasm.c b/gdb/disasm.c
index 81c466c188a..5d19dea72b6 100644
--- a/gdb/disasm.c
+++ b/gdb/disasm.c
@@ -375,10 +375,20 @@ gdb_pretty_print_disassembler::pretty_print_insn (const struct disasm_insn *insn
 	  m_uiout->field_string ("func-name", name,
 				 function_name_style.style ());
 	/* For negative offsets, avoid displaying them as +-N; the sign of
-	   the offset takes the place of the "+" here.  */
-	if (offset >= 0)
-	  m_uiout->text ("+");
-	m_uiout->field_signed ("offset", offset);
+	   the offset takes the place of the "+" here.  For MI consumers,
+       emit the integer value; otherwise, print the formatted offset based
+       on the current 'output-radix'.  */
+	if (m_uiout->is_mi_like_p ())
+	  {
+	    if (offset >= 0)
+	      m_uiout->text ("+");
+	    m_uiout->field_signed ("offset", offset);
+	  }
+	else
+	  {
+	    std::string s = format_pc_offset (offset);
+	    m_uiout->field_string ("offset", s.c_str ());
+	  }
 	m_uiout->text (">:\t");
       }
     else
diff --git a/gdb/printcmd.c b/gdb/printcmd.c
index ae498395436..5fb8c666447 100644
--- a/gdb/printcmd.c
+++ b/gdb/printcmd.c
@@ -567,7 +567,7 @@ print_address_symbolic (struct gdbarch *gdbarch, CORE_ADDR addr,
     gdb_puts ("<", stream);
   fputs_styled (name.c_str (), function_name_style.style (), stream);
   if (offset != 0)
-    gdb_printf (stream, "%+d", offset);
+    gdb_puts (format_pc_offset (offset).c_str (), stream);
 
   /* Append source filename and line number if desired.  Give specific
      line # of this addr, if we have it; else line # of the nearest symbol.  */
diff --git a/gdb/testsuite/gdb.base/radix.c b/gdb/testsuite/gdb.base/radix.c
new file mode 100644
index 00000000000..8a4d1287208
--- /dev/null
+++ b/gdb/testsuite/gdb.base/radix.c
@@ -0,0 +1,35 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2026 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <stdio.h>
+
+static int v;
+
+int
+main (void)
+{
+  v = 0;
+
+  puts ("hello world");
+
+  printf ("this is another string\n");
+
+  v += 3;
+
+  return v;
+}
diff --git a/gdb/testsuite/gdb.base/radix.exp b/gdb/testsuite/gdb.base/radix.exp
index 7a4320bbf36..4b8e2d74b49 100644
--- a/gdb/testsuite/gdb.base/radix.exp
+++ b/gdb/testsuite/gdb.base/radix.exp
@@ -17,6 +17,11 @@
 # This file was written by Fred Fish. (fnf@cygnus.com)
 # And rewritten by Michael Chastain (mec.gnu@mindspring.com)
 
+standard_testfile
+
+if {[build_executable "failed to prepare" $testfile $srcfile debug]} {
+    return -1
+}
 
 # Start with a fresh gdb.
 
@@ -189,3 +194,41 @@ gdb_test "set radix 7" \
 gdb_test "show output-radix" \
     "Default output radix for printing of values is 10\\." \
     "output radix unchanged after rejection through set radix command"
+
+with_test_prefix "pc offset radix" {
+    clean_restart $testfile
+
+    if { ![runto_main] } {
+      return -1
+    }
+
+    proc test_pc_offset_radix { oradix offset_re } {
+      global gdb_prompt
+
+      gdb_test "set output-radix $oradix" \
+	  "Output radix now set to decimal $oradix.*\\."
+
+      set test "x/i with output-radix $oradix"
+
+      gdb_test_multiple "x/i \$pc" "$test 1" {
+	-re -wrap "<main\\+$offset_re>:.*" {
+	   pass $gdb_test_name
+	}
+      }
+
+      gdb_test "ni 3" "\[0-9\]+.*" "Next instruction for radix $oradix"
+
+      gdb_test_multiple "x/i \$pc" "$test 2" {
+	-re -wrap "<main\\+$offset_re>:.*" {
+	   pass $gdb_test_name
+	}
+      }
+    }
+
+    test_pc_offset_radix 8  {0[0-7]+}
+    test_pc_offset_radix 10 {[1-9][0-9]*}
+    test_pc_offset_radix 16 {0x[0-9a-f]+}
+
+    gdb_test "set output-radix 10" "Output radix now set to decimal 10.*\\." \
+	"restore output-radix"
+}
diff --git a/gdb/valprint.c b/gdb/valprint.c
index 62b1b33bb66..d0d0472ca7a 100644
--- a/gdb/valprint.c
+++ b/gdb/valprint.c
@@ -171,6 +171,19 @@ show_output_radix (struct ui_file *file, int from_tty,
 	      value);
 }
 
+/* See valprint.h.  */
+
+std::string
+format_pc_offset (int offset)
+{
+  std::string sign = (offset < 0) ? "-" : "+";
+
+  std::string body = int_string (offset < 0 ? -offset : offset, output_radix,
+                                 0, 0, 1);
+
+  return sign + body;
+}
+
 /* By default we print arrays without printing the index of each element in
    the array.  This behavior can be changed by setting PRINT_ARRAY_INDEXES.  */
 
diff --git a/gdb/valprint.h b/gdb/valprint.h
index 0ce3e0781f6..5511707cba3 100644
--- a/gdb/valprint.h
+++ b/gdb/valprint.h
@@ -320,6 +320,12 @@ extern int build_address_symbolic (struct gdbarch *,
 				   int *line,
 				   int *unmapped);
 
+/* Format OFFSET, the offset portion of a "<symbol+offset>" display, as
+   a string with an explicit sign prefix ("+" or "-").  The numeric
+   portion is rendered using the current "output-radix".  */
+
+extern std::string format_pc_offset (int offset);
+
 /* Check to see if RECURSE is greater than or equal to the allowed
    printing max-depth (see 'set print max-depth').  If it is then print an
    ellipsis expression to STREAM and return true, otherwise return false.
-- 
2.54.0.563.g4f69b47b94-goog