diff --git a/programs/pkey/dh_server.c b/programs/pkey/dh_server.c
index 54165dc..b883653 100644
--- a/programs/pkey/dh_server.c
+++ b/programs/pkey/dh_server.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/pk_sign.c b/programs/pkey/pk_sign.c
index 3335575..2e9b2d8 100644
--- a/programs/pkey/pk_sign.c
+++ b/programs/pkey/pk_sign.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_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
diff --git a/programs/pkey/pk_verify.c b/programs/pkey/pk_verify.c
index a6d3481..bdeb559 100644
--- a/programs/pkey/pk_verify.c
+++ b/programs/pkey/pk_verify.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_BIGNUM_C) || !defined(MBEDTLS_MD_C) || \
diff --git a/programs/pkey/rsa_sign.c b/programs/pkey/rsa_sign.c
index 1308be2..8ba3e7d 100644
--- a/programs/pkey/rsa_sign.c
+++ b/programs/pkey/rsa_sign.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_BIGNUM_C) || !defined(MBEDTLS_RSA_C) ||  \
diff --git a/programs/pkey/rsa_sign_pss.c b/programs/pkey/rsa_sign_pss.c
index 643ac47..fe3de03 100644
--- a/programs/pkey/rsa_sign_pss.c
+++ b/programs/pkey/rsa_sign_pss.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_MD_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
diff --git a/programs/pkey/rsa_verify.c b/programs/pkey/rsa_verify.c
index f65883d..ccdf13e 100644
--- a/programs/pkey/rsa_verify.c
+++ b/programs/pkey/rsa_verify.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_BIGNUM_C) || !defined(MBEDTLS_RSA_C) ||  \
diff --git a/programs/pkey/rsa_verify_pss.c b/programs/pkey/rsa_verify_pss.c
index bc2ea64..d7efa65 100644
--- a/programs/pkey/rsa_verify_pss.c
+++ b/programs/pkey/rsa_verify_pss.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_MD_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
diff --git a/programs/psa/key_ladder_demo.c b/programs/psa/key_ladder_demo.c
index 084beb8..6059fb1 100644
--- a/programs/psa/key_ladder_demo.c
+++ b/programs/psa/key_ladder_demo.c
@@ -58,6 +58,7 @@
 
 #include "mbedtls/platform.h" // for mbedtls_setbuf
 #include "mbedtls/platform_util.h" // for mbedtls_platform_zeroize
+// md.h is included this early since MD_CAN_XXX macros are defined there.
 #include "mbedtls/md.h"
 
 #include <psa/crypto.h>
diff --git a/programs/x509/cert_req.c b/programs/x509/cert_req.c
index e651f3c..f35d629 100644
--- a/programs/x509/cert_req.c
+++ b/programs/x509/cert_req.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_X509_CSR_WRITE_C) || !defined(MBEDTLS_FS_IO) ||  \
diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 9ff9488..5c911ca 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.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_X509_CRT_WRITE_C) || \