From 3e7e509d5c42da54e6ba789530f089d1345cd5ad Mon Sep 17 00:00:00 2001
From: lhuang04 <lhuang04@fb.com>
Date: Thu, 9 Sep 2021 05:55:47 -0700
Subject: [PATCH] fix Wunused-but-set-variable warning/error
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Summary:
When the `MBEDTLS_DEBUG_C` is undefined, we saw the following compiler
warnining/error.

```
/upstream/library/ssl_tls13_keys.c: In function
‘mbedtls_ssl_tls1_3_generate_resumption_master_secret’:
/upstream/library/ssl_tls13_keys.c:890:12: error: variable
‘md_size’ set but not used [-Werror=unused-but-set-variable]
     size_t md_size;
```

```
/upstream/library/ssl_tls13_server.c: In function
‘ssl_parse_key_shares_ext’:
/upstream/library/ssl_tls13_server.c:366:39: error:
variable ‘their_curve_info’ set but not used
[-Werror=unused-but-set-variable]
         mbedtls_ecp_curve_info const *their_curve_info;
```

Test Plan:
```
rm -rf build/; mkdir build; cd build; CFLAGS="-std=c99 -g
-Wunused-but-set-variable -Wno-unused-parameter" cmake ..; make -j
```

Reviewers:

Subscribers:

Tasks:

Tags:
---
 library/ssl_tls13_keys.c   | 4 ++++
 library/ssl_tls13_server.c | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/library/ssl_tls13_keys.c b/library/ssl_tls13_keys.c
index b19504c2f631..afbeaebebbad 100644
--- a/library/ssl_tls13_keys.c
+++ b/library/ssl_tls13_keys.c
@@ -886,8 +886,10 @@ int mbedtls_ssl_tls1_3_generate_resumption_master_secret(
     int ret = 0;
 
     mbedtls_md_type_t md_type;
+#if defined(MBEDTLS_DEBUG_C)
     mbedtls_md_info_t const *md_info;
     size_t md_size;
+#endif /* MBEDTLS_DEBUG_C */
 
     unsigned char transcript[MBEDTLS_MD_MAX_SIZE];
     size_t transcript_len;
@@ -896,8 +898,10 @@ int mbedtls_ssl_tls1_3_generate_resumption_master_secret(
           ( "=> mbedtls_ssl_tls1_3_generate_resumption_master_secret" ) );
 
     md_type = ssl->handshake->ciphersuite_info->mac;
+#if defined(MBEDTLS_DEBUG_C)
     md_info = mbedtls_md_info_from_type( md_type );
     md_size = mbedtls_md_get_size( md_info );
+#endif /* MBEDTLS_DEBUG_C */
 
     ret = mbedtls_ssl_get_handshake_transcript( ssl, md_type,
                                                 transcript, sizeof( transcript ),
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 51977c79941c..7353ec06f99a 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -363,7 +363,9 @@ static int ssl_parse_key_shares_ext( mbedtls_ssl_context *ssl,
     {
         uint16_t their_group;
         mbedtls_ecp_group_id their_curve;
+#if defined(MBEDTLS_DEBUG_C)
         mbedtls_ecp_curve_info const *their_curve_info;
+#endif /* MBEDTLS_DEBUG_C */
         unsigned char const *end_of_share;
 
         /*
@@ -439,7 +441,9 @@ static int ssl_parse_key_shares_ext( mbedtls_ssl_context *ssl,
          * - Apply further curve checks
          */
 
+#if defined(MBEDTLS_DEBUG_C)
         their_curve_info = mbedtls_ecp_curve_info_from_grp_id( their_curve );
+#endif /* MBEDTLS_DEBUG_C */
         MBEDTLS_SSL_DEBUG_MSG( 2, ( "ECDH curve: %s", their_curve_info->name ) );
 
         ret = mbedtls_ecdh_setup( &ssl->handshake->ecdh_ctx, their_curve );