progress.c: silence cgcc suggestion about internal linkage

Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Reviewed-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/progress.c b/progress.c
index 19805ac..75633e9 100644
--- a/progress.c
+++ b/progress.c
@@ -8,6 +8,7 @@
  * published by the Free Software Foundation.
  */
 
+#define GIT_TEST_PROGRESS_ONLY
 #include "cache.h"
 #include "gettext.h"
 #include "progress.h"
@@ -52,7 +53,6 @@ static volatile sig_atomic_t progress_update;
  */
 int progress_testing;
 uint64_t progress_test_ns = 0;
-void progress_test_force_update(void); /* To silence -Wmissing-prototypes */
 void progress_test_force_update(void)
 {
 	progress_update = 1;
diff --git a/progress.h b/progress.h
index 8473389..f1913ac 100644
--- a/progress.h
+++ b/progress.h
@@ -3,6 +3,14 @@
 
 struct progress;
 
+#ifdef GIT_TEST_PROGRESS_ONLY
+
+extern int progress_testing;
+extern uint64_t progress_test_ns;
+void progress_test_force_update(void);
+
+#endif
+
 void display_throughput(struct progress *progress, uint64_t total);
 void display_progress(struct progress *progress, uint64_t n);
 struct progress *start_progress(const char *title, uint64_t total);
diff --git a/t/helper/test-progress.c b/t/helper/test-progress.c
index 42b96cb..5d05cbe 100644
--- a/t/helper/test-progress.c
+++ b/t/helper/test-progress.c
@@ -13,20 +13,13 @@
  *
  * See 't0500-progress-display.sh' for examples.
  */
+#define GIT_TEST_PROGRESS_ONLY
 #include "test-tool.h"
 #include "gettext.h"
 #include "parse-options.h"
 #include "progress.h"
 #include "strbuf.h"
 
-/*
- * These are defined in 'progress.c', but are not exposed in 'progress.h',
- * because they are exclusively for testing.
- */
-extern int progress_testing;
-extern uint64_t progress_test_ns;
-void progress_test_force_update(void);
-
 int cmd__progress(int argc, const char **argv)
 {
 	int total = 0;