Add an option autoload to PROXYSUBS, to generate an AUTOLOAD subroutine.

Like croak_on_error, this is only useful with the Proxy Constant Subroutine
code, as that adds all known constants to the symbol table at compile time.
The (obvious) additional restriction is that directly implementing AUTOLOAD
is only useful if the package wishes to perform no other autoloading, and to
treat all autoload requests as (failed) constant lookups (with errors describing
them as such).

1 files changed, 25 insertions, 7 deletions

diff --git a/cpan/ExtUtils-Constant/lib/ExtUtils/Constant/ProxySubs.pm b/cpan/ExtUtils-Constant/lib/ExtUtils/Constant/ProxySubs.pm
index 635cf48c3c..4f31f8ea02 100644
--- a/cpan/ExtUtils-Constant/lib/ExtUtils/Constant/ProxySubs.pm
+++ b/cpan/ExtUtils-Constant/lib/ExtUtils/Constant/ProxySubs.pm
@@ -171,9 +171,17 @@ sub WriteConstants {
     $options = {} unless ref $options;
     my $explosives = $options->{croak_on_read};
     my $croak_on_error = $options->{croak_on_error};
-    # Until someone patches this (with test cases):
-    carp ("PROXYSUBS options 'croak_on_read' and 'croak_on_error' cannot be used together")
-	if $explosives && $croak_on_error; 
+    my $autoload = $options->{autoload};
+    {
+	my $exclusive = 0;
+	++$exclusive if $explosives;
+	++$exclusive if $croak_on_error;
+	++$exclusive if $autoload;
+
+	# Until someone patches this (with test cases):
+	carp ("PROXYSUBS options 'autoload', 'croak_on_read' and 'croak_on_error' cannot be used together")
+	    if $exclusive > 1;
+    }
     # Strictly it requires Perl_caller_cx
     carp ("PROXYSUBS options 'croak_on_error' requires v5.13.5 or later")
 	if $croak_on_error && $^V < v5.13.5;
@@ -526,18 +534,28 @@ EOBOOT
 EOBOOT
     }
 
-    if ($croak_on_error) {
-        print $xs_fh <<"EOC";
+    if ($croak_on_error || $autoload) {
+        print $xs_fh $croak_on_error ? <<"EOC" : <<'EOA';
 
 void
 $xs_subname(sv)
+    INPUT:
+	SV *		sv;
     PREINIT:
 	const PERL_CONTEXT *cx = caller_cx(0, NULL);
 	/* cx is NULL if we've been called from the top level. PL_curcop isn't
 	   ideal, but it's much cheaper than other ways of not going SEGV.  */
 	const COP *cop = cx ? cx->blk_oldcop : PL_curcop;
-    INPUT:
-	SV *		sv;
+EOC
+
+void
+AUTOLOAD()
+    PROTOTYPE: DISABLE
+    PREINIT:
+	SV *sv = newSVpvn_flags(SvPVX(cv), SvCUR(cv), SVs_TEMP | SvUTF8(cv));
+	const COP *cop = PL_curcop;
+EOA
+        print $xs_fh <<"EOC";
     PPCODE:
 #ifndef SYMBIAN
 	HV *${c_subname}_missing = get_missing_hash(aTHX);