Revert "Remove mathoms stub Perl_gv_SVadd()"

This reverts commit f2cb455.

Author: khwilliamson

embed.fnc

@@ -4203,7 +4203,7 @@ Mp	|bool	|do_exec	|NN const char *cmd
 p	|bool	|do_exec	|NN const char *cmd
 #endif
 #if defined(PERL_DONT_CREATE_GVSV)
-Admp	|GV *	|gv_SVadd	|NULLOK GV *gv
+AMbdp	|GV *	|gv_SVadd	|NULLOK GV *gv
 #endif
 #if defined(PERL_IMPLICIT_SYS)
 CTo	|PerlInterpreter *|perl_alloc_using				\

embed.h

@@ -2060,9 +2060,6 @@
 #   define finalize_optree(a)                   Perl_finalize_optree(aTHX_ a)
 #   define optimize_optree(a)                   Perl_optimize_optree(aTHX_ a)
 # endif
-# if defined(PERL_DONT_CREATE_GVSV)
-#   define gv_SVadd(a)                          Perl_gv_SVadd(aTHX,a)
-# endif
 # if !defined(PERL_IMPLICIT_SYS)
 #   define my_pclose(a)                         Perl_my_pclose(aTHX_ a)
 #   define my_popen(a,b)                        Perl_my_popen(aTHX_ a,b)

gv.h

@@ -346,7 +346,7 @@ Make sure there is a slot of the given type (AV, HV, IO, SV) in the GV C<gv>.
 #define gv_AVadd(gv) gv_add_by_type((gv), SVt_PVAV)
 #define gv_HVadd(gv) gv_add_by_type((gv), SVt_PVHV)
 #define gv_IOadd(gv) gv_add_by_type((gv), SVt_PVIO)
-#define Perl_gv_SVadd(mTHX, gv)  Perl_gv_add_by_type(aTHX_ (gv), SVt_NULL)
+#define gv_SVadd(gv) gv_add_by_type((gv), SVt_NULL)
 
 /*
  * ex: set ts=8 sts=4 sw=4 et:

mathoms.c

@@ -666,6 +666,14 @@ Perl_save_op(pTHX)
     save_op();
 }
 
+#ifdef PERL_DONT_CREATE_GVSV
+GV *
+Perl_gv_SVadd(pTHX_ GV *gv)
+{
+    return gv_SVadd(gv);
+}
+#endif
+
 GV *
 Perl_gv_AVadd(pTHX_ GV *gv)
 {