diff -up gnupg-2.2.19/agent/agent.h.build gnupg-2.2.19/agent/agent.h
--- gnupg-2.2.19/agent/agent.h.build	2019-07-09 11:08:44.000000000 +0200
+++ gnupg-2.2.19/agent/agent.h	2020-01-30 16:13:05.470939005 +0100
@@ -37,6 +37,14 @@
 #include "../common/session-env.h"
 #include "../common/shareddefs.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
+
 /* To convey some special hash algorithms we use algorithm numbers
    reserved for application use. */
 #ifndef GCRY_MODULE_ID_USER
@@ -55,6 +63,7 @@
 
 
 /* A large struct name "opt" to keep global flags */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   unsigned int debug;  /* Debug flags (DBG_foo_VALUE) */
diff -up gnupg-2.2.19/agent/gpg-agent.c.build gnupg-2.2.19/agent/gpg-agent.c
--- gnupg-2.2.19/agent/gpg-agent.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/agent/gpg-agent.c	2020-01-30 15:43:43.566456867 +0100
@@ -49,6 +49,7 @@
 #endif
 #include <npth.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #define GNUPG_COMMON_NEED_AFLOCAL
 #include "agent.h"
 #include <assuan.h> /* Malloc hooks  and socket wrappers. */
diff -up gnupg-2.2.19/agent/preset-passphrase.c.build gnupg-2.2.19/agent/preset-passphrase.c
--- gnupg-2.2.19/agent/preset-passphrase.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/agent/preset-passphrase.c	2020-01-30 16:01:05.992812177 +0100
@@ -44,6 +44,7 @@
 # include <windows.h>  /* To initialize the sockets.  fixme */
 #endif
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "agent.h"
 #include "../common/simple-pwquery.h"
 #include "../common/i18n.h"
diff -up gnupg-2.2.19/agent/protect-tool.c.build gnupg-2.2.19/agent/protect-tool.c
--- gnupg-2.2.19/agent/protect-tool.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/agent/protect-tool.c	2020-01-30 16:00:35.188363339 +0100
@@ -38,6 +38,7 @@
 #include <fcntl.h> /* for setmode() */
 #endif
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "agent.h"
 #include "../common/i18n.h"
 #include "../common/get-passphrase.h"
diff -up gnupg-2.2.19/agent/t-protect.c.build gnupg-2.2.19/agent/t-protect.c
--- gnupg-2.2.19/agent/t-protect.c.build	2017-12-08 07:40:06.000000000 +0100
+++ gnupg-2.2.19/agent/t-protect.c	2020-01-30 16:01:22.903509604 +0100
@@ -23,6 +23,7 @@
 #include <stdlib.h>
 #include <assert.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "agent.h"
 
 
diff -up gnupg-2.2.19/common/iobuf.c.build gnupg-2.2.19/common/iobuf.c
--- gnupg-2.2.19/common/iobuf.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/common/iobuf.c	2020-01-29 19:10:03.488980061 +0100
@@ -118,6 +118,7 @@ struct close_cache_s
 typedef struct close_cache_s *close_cache_t;
 static close_cache_t close_cache;
 
+int iobuf_debug_mode;
 
 
 #ifdef HAVE_W32_SYSTEM
diff -up gnupg-2.2.19/common/iobuf.h.build gnupg-2.2.19/common/iobuf.h
--- gnupg-2.2.19/common/iobuf.h.build	2017-02-24 13:46:24.000000000 +0100
+++ gnupg-2.2.19/common/iobuf.h	2020-01-30 10:14:21.404483909 +0100
@@ -249,14 +249,7 @@ struct iobuf_struct
   int subno;
 };
 
-#ifndef EXTERN_UNLESS_MAIN_MODULE
-#if defined (__riscos__) && !defined (INCLUDED_BY_MAIN_MODULE)
-#define EXTERN_UNLESS_MAIN_MODULE extern
-#else
-#define EXTERN_UNLESS_MAIN_MODULE
-#endif
-#endif
-EXTERN_UNLESS_MAIN_MODULE int iobuf_debug_mode;
+extern int iobuf_debug_mode;
 
 
 /* Returns whether the specified filename corresponds to a pipe.  In
diff -up gnupg-2.2.19/dirmngr/dirmngr.c.build gnupg-2.2.19/dirmngr/dirmngr.c
--- gnupg-2.2.19/dirmngr/dirmngr.c.build	2019-11-12 20:14:44.000000000 +0100
+++ gnupg-2.2.19/dirmngr/dirmngr.c	2020-01-30 16:30:39.650080724 +0100
@@ -55,6 +55,7 @@
 #endif /*HTTP_USE_GNUTLS*/
 
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #define GNUPG_COMMON_NEED_AFLOCAL
 #include "dirmngr.h"
 
diff -up gnupg-2.2.19/dirmngr/dirmngr.h.build gnupg-2.2.19/dirmngr/dirmngr.h
--- gnupg-2.2.19/dirmngr/dirmngr.h.build	2019-11-18 18:44:30.000000000 +0100
+++ gnupg-2.2.19/dirmngr/dirmngr.h	2020-01-30 16:30:12.250570852 +0100
@@ -39,6 +39,14 @@
 #include "dirmngr-status.h"
 #include "http.h"     /* (parsed_uri_t) */
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
+
 /* This objects keeps information about a particular LDAP server and
    is used as item of a single linked list of servers. */
 struct ldap_server_s
@@ -76,6 +84,7 @@ struct fingerprint_list_s
 
 
 /* A large struct named "opt" to keep global flags.  */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   unsigned int debug; /* debug flags (DBG_foo_VALUE) */
diff -up gnupg-2.2.19/g10/gpgcompose.c.build gnupg-2.2.19/g10/gpgcompose.c
--- gnupg-2.2.19/g10/gpgcompose.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/g10/gpgcompose.c	2020-01-30 10:06:13.924966959 +0100
@@ -20,6 +20,7 @@
 #include <config.h>
 #include <errno.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "gpg.h"
 #include "packet.h"
 #include "keydb.h"
diff -up gnupg-2.2.19/g10/options.h.build gnupg-2.2.19/g10/options.h
--- gnupg-2.2.19/g10/options.h.build	2020-01-29 12:54:10.308621663 +0100
+++ gnupg-2.2.19/g10/options.h	2020-01-29 19:10:44.659238547 +0100
@@ -32,7 +32,7 @@
 
 #ifndef EXTERN_UNLESS_MAIN_MODULE
 /* Norcraft can't cope with common symbols */
-#if defined (__riscos__) && !defined (INCLUDED_BY_MAIN_MODULE)
+#if !defined (INCLUDED_BY_MAIN_MODULE)
 #define EXTERN_UNLESS_MAIN_MODULE extern
 #else
 #define EXTERN_UNLESS_MAIN_MODULE
diff -up gnupg-2.2.19/g10/test.c.build gnupg-2.2.19/g10/test.c
--- gnupg-2.2.19/g10/test.c.build	2017-02-10 17:24:08.000000000 +0100
+++ gnupg-2.2.19/g10/test.c	2020-01-30 10:06:33.522624663 +0100
@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "gpg.h"
 
 /* A unit test consists of one or more tests.  Tests can be broken
diff -up gnupg-2.2.19/g13/g13.c.build gnupg-2.2.19/g13/g13.c
--- gnupg-2.2.19/g13/g13.c.build	2017-08-28 12:22:54.000000000 +0200
+++ gnupg-2.2.19/g13/g13.c	2020-01-30 16:18:25.927205688 +0100
@@ -27,6 +27,7 @@
 #include <fcntl.h>
 #include <npth.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "g13.h"
 
 #include <gcrypt.h>
diff -up gnupg-2.2.19/g13/g13-common.h.build gnupg-2.2.19/g13/g13-common.h
--- gnupg-2.2.19/g13/g13-common.h.build	2017-08-28 12:22:54.000000000 +0200
+++ gnupg-2.2.19/g13/g13-common.h	2020-01-30 16:20:02.257482517 +0100
@@ -32,6 +32,13 @@
 #include "../common/session-env.h"
 #include "../common/strlist.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
 
 /* Debug values and macros.  */
 #define DBG_MOUNT_VALUE     1	/* Debug mount or device stuff. */
@@ -48,6 +55,7 @@
 /* A large struct named "opt" to keep global flags.  Note that this
    struct is used by g13 and g13-syshelp and thus some fields may only
    make sense for one of them.  */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   unsigned int debug; /* Debug flags (DBG_foo_VALUE).  */
diff -up gnupg-2.2.19/g13/g13-syshelp.c.build gnupg-2.2.19/g13/g13-syshelp.c
--- gnupg-2.2.19/g13/g13-syshelp.c.build	2017-08-28 12:22:54.000000000 +0200
+++ gnupg-2.2.19/g13/g13-syshelp.c	2020-01-30 16:18:15.861385748 +0100
@@ -31,6 +31,7 @@
 #endif
 #include <unistd.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "g13-syshelp.h"
 
 #include <gcrypt.h>
diff -up gnupg-2.2.19/scd/scdaemon.c.build gnupg-2.2.19/scd/scdaemon.c
--- gnupg-2.2.19/scd/scdaemon.c.build	2020-01-29 12:54:10.340621101 +0100
+++ gnupg-2.2.19/scd/scdaemon.c	2020-01-30 16:13:38.942340121 +0100
@@ -37,6 +37,7 @@
 #include <signal.h>
 #include <npth.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #define GNUPG_COMMON_NEED_AFLOCAL
 #include "scdaemon.h"
 #include <ksba.h>
diff -up gnupg-2.2.19/scd/scdaemon.h.build gnupg-2.2.19/scd/scdaemon.h
--- gnupg-2.2.19/scd/scdaemon.h.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/scd/scdaemon.h	2020-01-30 16:12:58.986055034 +0100
@@ -31,6 +31,14 @@
 #include "../common/util.h"
 #include "../common/sysutils.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
+
 /* To convey some special hash algorithms we use algorithm numbers
    reserved for application use. */
 #ifndef GCRY_MODULE_ID_USER
@@ -44,6 +52,7 @@
 
 
 /* A large struct name "opt" to keep global flags. */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   unsigned int debug; /* Debug flags (DBG_foo_VALUE). */
diff -up gnupg-2.2.19/sm/gpgsm.c.build gnupg-2.2.19/sm/gpgsm.c
--- gnupg-2.2.19/sm/gpgsm.c.build	2020-01-29 12:54:10.306621698 +0100
+++ gnupg-2.2.19/sm/gpgsm.c	2020-01-30 10:24:17.199619771 +0100
@@ -28,6 +28,8 @@
 #include <fcntl.h>
 /*#include <mcheck.h>*/
 
+#define INCLUDED_BY_MAIN_MODULE 1
+
 #include "gpgsm.h"
 #include <gcrypt.h>
 #include <assuan.h> /* malloc hooks */
diff -up gnupg-2.2.19/sm/gpgsm.h.build gnupg-2.2.19/sm/gpgsm.h
--- gnupg-2.2.19/sm/gpgsm.h.build	2019-12-06 20:32:57.000000000 +0100
+++ gnupg-2.2.19/sm/gpgsm.h	2020-01-30 15:36:11.325545926 +0100
@@ -36,6 +36,13 @@
 #include "../common/ksba-io-support.h"
 #include "../common/compliance.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
 
 #define MAX_DIGEST_LEN 64
 
@@ -52,7 +59,7 @@ struct keyserver_spec
 
 
 /* A large struct named "opt" to keep global flags. */
-struct
+EXTERN_UNLESS_MAIN_MODULE struct
 {
   unsigned int debug; /* debug flags (DBG_foo_VALUE) */
   int verbose;      /* verbosity level */
diff -up gnupg-2.2.19/tools/gpgconf.c.build gnupg-2.2.19/tools/gpgconf.c
--- gnupg-2.2.19/tools/gpgconf.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/tools/gpgconf.c	2020-01-30 16:42:05.759830715 +0100
@@ -25,6 +25,7 @@
 #include <string.h>
 #include <unistd.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "gpgconf.h"
 #include "../common/i18n.h"
 #include "../common/sysutils.h"
diff -up gnupg-2.2.19/tools/gpgconf.h.build gnupg-2.2.19/tools/gpgconf.h
--- gnupg-2.2.19/tools/gpgconf.h.build	2019-02-26 13:15:58.000000000 +0100
+++ gnupg-2.2.19/tools/gpgconf.h	2020-01-30 16:41:48.570137395 +0100
@@ -22,7 +22,16 @@
 
 #include "../common/util.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
+
 /* We keep all global options in the structure OPT.  */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   int verbose;		/* Verbosity level.  */
diff -up gnupg-2.2.19/tools/gpgtar.c.build gnupg-2.2.19/tools/gpgtar.c
--- gnupg-2.2.19/tools/gpgtar.c.build	2019-03-07 10:56:18.000000000 +0100
+++ gnupg-2.2.19/tools/gpgtar.c	2020-01-30 16:53:24.787712030 +0100
@@ -34,6 +34,7 @@
 #include <string.h>
 #include <assert.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "../common/util.h"
 #include "../common/i18n.h"
 #include "../common/sysutils.h"
diff -up gnupg-2.2.19/tools/gpgtar.h.build gnupg-2.2.19/tools/gpgtar.h
--- gnupg-2.2.19/tools/gpgtar.h.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/tools/gpgtar.h	2020-01-30 16:54:07.348951287 +0100
@@ -23,7 +23,16 @@
 #include "../common/util.h"
 #include "../common/strlist.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
+
 /* We keep all global options in the structure OPT.  */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   int verbose;
diff -up gnupg-2.2.19/tools/gpg-wks-client.c.build gnupg-2.2.19/tools/gpg-wks-client.c
--- gnupg-2.2.19/tools/gpg-wks-client.c.build	2019-07-09 11:08:45.000000000 +0200
+++ gnupg-2.2.19/tools/gpg-wks-client.c	2020-01-30 16:39:54.755167950 +0100
@@ -25,6 +25,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "../common/util.h"
 #include "../common/status.h"
 #include "../common/i18n.h"
diff -up gnupg-2.2.19/tools/gpg-wks.h.build gnupg-2.2.19/tools/gpg-wks.h
--- gnupg-2.2.19/tools/gpg-wks.h.build	2019-03-25 15:14:32.000000000 +0100
+++ gnupg-2.2.19/tools/gpg-wks.h	2020-01-30 16:40:52.412139301 +0100
@@ -25,11 +25,20 @@
 #include "../common/strlist.h"
 #include "mime-maker.h"
 
+#ifndef EXTERN_UNLESS_MAIN_MODULE
+#if !defined (INCLUDED_BY_MAIN_MODULE)
+#define EXTERN_UNLESS_MAIN_MODULE extern
+#else
+#define EXTERN_UNLESS_MAIN_MODULE
+#endif
+#endif
+
 /* The draft version we implement.  */
 #define WKS_DRAFT_VERSION 3
 
 
 /* We keep all global options in the structure OPT.  */
+EXTERN_UNLESS_MAIN_MODULE
 struct
 {
   int verbose;
diff -up gnupg-2.2.19/tools/gpg-wks-server.c.build gnupg-2.2.19/tools/gpg-wks-server.c
--- gnupg-2.2.19/tools/gpg-wks-server.c.build	2019-03-25 14:41:44.000000000 +0100
+++ gnupg-2.2.19/tools/gpg-wks-server.c	2020-01-30 16:40:05.052984229 +0100
@@ -32,6 +32,7 @@
 #include <sys/stat.h>
 #include <dirent.h>
 
+#define INCLUDED_BY_MAIN_MODULE 1
 #include "../common/util.h"
 #include "../common/init.h"
 #include "../common/sysutils.h"