diff --git a/library/debug.c b/library/debug.c
index 070f63a..4752ab1 100644
--- a/library/debug.c
+++ b/library/debug.c
@@ -42,7 +42,8 @@
 #define mbedtls_snprintf    snprintf
 #endif
 
-#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && !defined(inline)
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
 #define inline __inline
 #endif
 
diff --git a/library/ecp.c b/library/ecp.c
index 858540b..64a47ab 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -62,7 +62,8 @@
 #define mbedtls_free       free
 #endif
 
-#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && !defined(inline)
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
 #define inline __inline
 #endif
 
diff --git a/library/ecp_curves.c b/library/ecp_curves.c
index 68323c5..9a6e8eb 100644
--- a/library/ecp_curves.c
+++ b/library/ecp_curves.c
@@ -31,7 +31,8 @@
 
 #include <string.h>
 
-#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && !defined(inline)
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
 #define inline __inline
 #endif