Merge pull request #2873 from gilles-peskine-arm/bk-warning-fixes-x509

Fix some possibly-undefined variable warnings
diff --git a/ChangeLog b/ChangeLog
index 07880b2..aadc9e9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,8 @@
    * Fix an unchecked call to mbedtls_md() in the x509write module.
    * Fix build failure with MBEDTLS_ZLIB_SUPPORT enabled. Reported by
      Jack Lloyd in #2859. Fix submitted by jiblime in #2963.
+   * Fix some false-positive uninitialized variable warnings in X.509. Fix
+     contributed by apple-ihack-geek in #2663.
 
 = mbed TLS 2.20.0 branch released 2020-01-15
 
@@ -86,8 +88,6 @@
    * mbedtls_ctr_drbg_set_entropy_len() and
      mbedtls_hmac_drbg_set_entropy_len() now work if you call them before
      mbedtls_ctr_drbg_seed() or mbedtls_hmac_drbg_seed().
-   * Fix some false-positive uninitialized variable warnings. Fix contributed
-     by apple-ihack-geek in #2663.
 
 Changes
    * Remove the technical possibility to define custom mbedtls_md_info
@@ -119,6 +119,10 @@
      mbedtls_ssl_export_keys_ext_t, so that the key exporter is discouraged
      from modifying the client/server hello.
 
+Bugfix
+   * Fix some false-positive uninitialized variable warnings in crypto. Fix
+     contributed by apple-ihack-geek in #2663.
+
 = mbed TLS 2.19.0 branch released 2019-09-06
 
 Security
diff --git a/library/x509_crl.c b/library/x509_crl.c
index d1176fc..371c446 100644
--- a/library/x509_crl.c
+++ b/library/x509_crl.c
@@ -541,7 +541,7 @@
 {
 #if defined(MBEDTLS_PEM_PARSE_C)
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t use_len;
+    size_t use_len = 0;
     mbedtls_pem_context pem;
     int is_pem = 0;
 
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 38e69cc..1e47230 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -2538,7 +2538,7 @@
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     mbedtls_x509_crt *parent, *fallback_parent;
-    int signature_is_good, fallback_signature_is_good;
+    int signature_is_good = 0, fallback_signature_is_good;
 
 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
     /* did we have something in progress? */