diff --git a/gv.c b/gv.c
index e4bd3943c189..65c29717c03e 100644
--- a/gv.c
+++ b/gv.c
@@ -121,9 +121,9 @@ Perl_gv_fetchfile_flags(pTHX_ const char *const name, const STRLEN namelen,
 #else
 	sv_setpvn(GvSV(gv), name, namelen);
 #endif
-	if (PERLDB_LINE || PERLDB_SAVESRC)
-	    hv_magic(GvHVn(gv_AVadd(gv)), NULL, PERL_MAGIC_dbfile);
     }
+    if ((PERLDB_LINE || PERLDB_SAVESRC) && !GvAV(gv))
+	    hv_magic(GvHVn(gv_AVadd(gv)), NULL, PERL_MAGIC_dbfile);
     if (tmpbuf != smallbuf)
 	Safefree(tmpbuf);
     return gv;
diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index aa23407740d0..1d2609542f58 100644
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -387,6 +387,13 @@ Parsing Perl code (either with string C<eval> or by loading modules) from
 within a C<UNITCHECK> block no longer causes the interpreter to crash
 L<[perl #70614]|http://rt.perl.org/rt3//Public/Bug/Display.html?id=70614>.
 
+=item *
+
+When C<-d> is used on the shebang (C<#!>) line, the debugger now has access
+to the lines of the main program. In the past, this sometimes worked and
+sometimes did not, depending on what order things happened to be arranged
+in memory.
+
 =back
 
 =head1 Known Problems
diff --git a/t/run/switchd.t b/t/run/switchd.t
index 921b966073cc..f937093809a6 100644
--- a/t/run/switchd.t
+++ b/t/run/switchd.t
@@ -9,7 +9,7 @@ BEGIN { require "./test.pl"; }
 
 # This test depends on t/lib/Devel/switchd.pm.
 
-plan(tests => 2);
+plan(tests => 3);
 
 my $r;
 
@@ -44,3 +44,16 @@ __SWDTEST__
     like($r, qr/^sub<Devel::switchd::import>;import<Devel::switchd a 42>;DB<main,$::tempfile_regexp,9>;sub<Foo::foo>;DB<Foo,$::tempfile_regexp,5>;DB<Foo,$::tempfile_regexp,6>;DB<Foo,$::tempfile_regexp,6>;sub<Bar::bar>;DB<Bar,$::tempfile_regexp,2>;sub<Bar::bar>;DB<Bar,$::tempfile_regexp,2>;sub<Bar::bar>;DB<Bar,$::tempfile_regexp,2>;$/);
 }
 
+# [perl #71806]
+cmp_ok(
+  runperl(       # less is useful for something :-)
+   switches => [ '"-Mless ++INC->{q-Devel/_.pm-}"' ],
+   progs    => [
+    '#!perl -d:_',
+    'sub DB::DB{} print scalar @{q/_</.__FILE__}',
+   ],
+  ),
+ '>',
+  0,
+ 'The debugger can see the lines of the main program under #!perl -d',
+);