Account for octal marker in %#o format

stdio-common/Makefile

@@ -206,6 +206,7 @@ tests := \
   tst-printf-bz25691 \
   tst-printf-fp-free \
   tst-printf-fp-leak \
+  tst-printf-oct \
   tst-printf-round \
   tst-printfsz \
   tst-put-error \

stdio-common/tst-printf-oct.c

@@ -0,0 +1,49 @@
+/* Test printf width padding with octal format
+   Copyright (C) 2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <support/check.h>
+#include <support/support.h>
+
+static int
+do_test (void)
+{
+  char buf[80];
+
+  sprintf (buf, "%-7o", 123);
+  TEST_COMPARE_STRING (buf, "173    ");
+
+  sprintf (buf, "%#-7o", 123);
+  TEST_COMPARE_STRING (buf, "0173   ");
+
+  sprintf (buf, "%7o", 123);
+  TEST_COMPARE_STRING (buf, "    173");
+
+  sprintf (buf, "%#7o", 123);
+  TEST_COMPARE_STRING (buf, "   0173");
+
+  sprintf (buf, "%07o", 123);
+  TEST_COMPARE_STRING (buf, "0000173");
+
+  sprintf (buf, "%#07o", 123);
+  TEST_COMPARE_STRING (buf, "0000173");
+
+  return 0;
+}
+
+#include <support/test-driver.c>

stdio-common/vfprintf-process-arg.c

@@ -196,6 +196,9 @@ LABEL (unsigned_number):      /* Unsigned number of base BASE.  */
         /* Account for 0X, 0x, 0B or 0b hex or binary marker.  */
         width -= 2;
 
+      if (octal_marker)
+        --width;
+
       if (is_negative || showsign || space)
         --width;
 
@@ -257,6 +260,9 @@ LABEL (unsigned_number):      /* Unsigned number of base BASE.  */
           width -= 2;
         }
 
+      if (octal_marker)
+	--width;
+
       width -= workend - string + prec;
 
       Xprintf_buffer_pad (buf, L_('0'), prec);