diff --git a/library/common.h b/library/common.h
index c3847cdbf6..e502b5de13 100644
--- a/library/common.h
+++ b/library/common.h
@@ -414,7 +414,7 @@ extern void (*mbedtls_test_hook_test_fail)( const char * test, int line, const c
  * \param   b Pointer to input (buffer of at least \p n bytes)
  * \param   n Number of bytes to process.
  */
-static inline void mbedtls_xor( unsigned char *r, unsigned char const *a, unsigned char const *b, size_t n )
+inline void mbedtls_xor( unsigned char *r, unsigned char const *a, unsigned char const *b, size_t n )
 {
 #if defined(MBEDTLS_ALLOW_UNALIGNED_ACCESS)
     uint32_t *a32 = (uint32_t *)a;
diff --git a/library/platform_util.c b/library/platform_util.c
index 916a7f444c..8fba664d27 100644
--- a/library/platform_util.c
+++ b/library/platform_util.c
@@ -143,3 +143,8 @@ struct tm *mbedtls_platform_gmtime_r( const mbedtls_time_t *tt,
 void (*mbedtls_test_hook_test_fail)( const char *, int, const char *);
 #endif /* MBEDTLS_TEST_HOOKS */
 
+/*
+ * Provide an external definition of mbedtls_xor so that the compiler
+ * has the option to not inline it
+ */
+extern inline void mbedtls_xor( unsigned char *r, unsigned char const *a, unsigned char const *b, size_t n );