diff --git a/programs/pkey/dh_client.c b/programs/pkey/dh_client.c
index be0b6e9f60..5a2c30fc21 100644
--- a/programs/pkey/dh_client.c
+++ b/programs/pkey/dh_client.c
@@ -20,6 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if defined(MBEDTLS_AES_C) && defined(MBEDTLS_DHM_C) && \
diff --git a/programs/pkey/dh_server.c b/programs/pkey/dh_server.c
index b883653eb7..c940be0c0f 100644
--- a/programs/pkey/dh_server.c
+++ b/programs/pkey/dh_server.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if defined(MBEDTLS_AES_C) && defined(MBEDTLS_DHM_C) && \
diff --git a/programs/pkey/pk_sign.c b/programs/pkey/pk_sign.c
index 2e9b2d8378..82cb6a1d66 100644
--- a/programs/pkey/pk_sign.c
+++ b/programs/pkey/pk_sign.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
diff --git a/programs/pkey/pk_verify.c b/programs/pkey/pk_verify.c
index bdeb559eb0..0c549e06e7 100644
--- a/programs/pkey/pk_verify.c
+++ b/programs/pkey/pk_verify.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_MD_C) || \
diff --git a/programs/pkey/rsa_sign.c b/programs/pkey/rsa_sign.c
index 8ba3e7d1f2..64375e9e70 100644
--- a/programs/pkey/rsa_sign.c
+++ b/programs/pkey/rsa_sign.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) ||  \
diff --git a/programs/pkey/rsa_sign_pss.c b/programs/pkey/rsa_sign_pss.c
index fe3de0309a..03882cd2f4 100644
--- a/programs/pkey/rsa_sign_pss.c
+++ b/programs/pkey/rsa_sign_pss.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_MD_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
diff --git a/programs/pkey/rsa_verify.c b/programs/pkey/rsa_verify.c
index ccdf13eb48..d525010dfa 100644
--- a/programs/pkey/rsa_verify.c
+++ b/programs/pkey/rsa_verify.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) ||  \
diff --git a/programs/pkey/rsa_verify_pss.c b/programs/pkey/rsa_verify_pss.c
index d7efa6549d..e21e92749b 100644
--- a/programs/pkey/rsa_verify_pss.c
+++ b/programs/pkey/rsa_verify_pss.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_MD_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
diff --git a/programs/x509/cert_req.c b/programs/x509/cert_req.c
index f35d62963a..396aaf3f8a 100644
--- a/programs/x509/cert_req.c
+++ b/programs/x509/cert_req.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_X509_CSR_WRITE_C) || !defined(MBEDTLS_FS_IO) ||  \
diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 5c911ca758..a822684241 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.c
@@ -20,7 +20,7 @@
 #include "mbedtls/build_info.h"
 
 #include "mbedtls/platform.h"
-// md.h is included this early since MD_CAN_XXX macros are defined there.
+/* md.h is included this early since MD_CAN_XXX macros are defined there. */
 #include "mbedtls/md.h"
 
 #if !defined(MBEDTLS_X509_CRT_WRITE_C) || \