diff --git a/debian/copyright b/debian/copyright
index da506585..c714f1f2 100644
--- a/debian/copyright
+++ b/debian/copyright
@@ -30,7 +30,7 @@ Files:     osmoappdesc.py
 Copyright: 2013 by Katerina Barone-Adesi <kat.obsc@gmail.com>
 License:   GPL-3.0+
 
-Files:     src/gprs_debug.cpp
+Files:     src/gprs_debug.c
            src/gprs_debug.h
            src/pcu_main.cpp
            src/pcu_l1_if.h
diff --git a/src/Makefile.am b/src/Makefile.am
index ccc40ac3..e7e94e0c 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -39,7 +39,7 @@ AM_LDFLAGS = -lrt
 noinst_LTLIBRARIES = libgprs.la
 
 libgprs_la_SOURCES = \
-	gprs_debug.cpp \
+	gprs_debug.c \
 	csn1.c \
 	csn1_dec.c \
 	csn1_enc.c \
diff --git a/src/gprs_debug.cpp b/src/gprs_debug.c
similarity index 97%
rename from src/gprs_debug.cpp
rename to src/gprs_debug.c
index 61c1c87e..03ef0830 100644
--- a/src/gprs_debug.cpp
+++ b/src/gprs_debug.c
@@ -1,7 +1,8 @@
-/* gprs_debug.cpp
+/* gprs_debug.c
  *
  * Copyright (C) 2012 Ivan Klyuchnikov
  * Copyright (C) 2019 Harald Welte <laforge@gnumonks.org>
+ * Copyright (C) 2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -14,10 +15,8 @@
  * GNU General Public License for more details.
  */
 
-extern "C" {
 #include <osmocom/core/utils.h>
 #include <osmocom/core/logging.h>
-}
 
 #include <gprs_debug.h>
 
diff --git a/src/gprs_debug.h b/src/gprs_debug.h
index b683a634..320c7399 100644
--- a/src/gprs_debug.h
+++ b/src/gprs_debug.h
@@ -19,9 +19,6 @@
 extern "C" {
 #endif
 #include <osmocom/core/logging.h>
-#ifdef __cplusplus
-};
-#endif
 
 /* we used to have DBSSGP definded in each application, and applications telling
  * libosmogb which sub-system to use.  That creates problems and has been deprecated */
@@ -48,3 +45,7 @@ enum {
 };
 
 extern const struct log_info gprs_log_info;
+
+#ifdef __cplusplus
+};
+#endif