diff --git a/src/Dict.h b/src/Dict.h
index b53c7e6c99..3d82b5418f 100644
--- a/src/Dict.h
+++ b/src/Dict.h
@@ -628,7 +628,7 @@ public:
             if ( max_entries < num_entries )
                 max_entries = num_entries;
             if ( num_entries > ThresholdEntries() )
-                SizeUp();
+                SizeUp(); // NOLINT(bugprone-branch-clone)
 
             // if space_distance is too great, performance decreases. we need to sizeup for
             // performance.
diff --git a/src/IP.h b/src/IP.h
index 5527fee3e8..4364676518 100644
--- a/src/IP.h
+++ b/src/IP.h
@@ -366,7 +366,7 @@ public:
      */
     const ip6_mobility* MobilityHeader() const {
         if ( ip4 )
-            return nullptr;
+            return nullptr; // NOLINT(bugprone-branch-clone)
         else if ( (*ip6_hdrs)[ip6_hdrs->Size() - 1]->Type() != IPPROTO_MOBILITY )
             return nullptr;
         else
diff --git a/src/strings.bif b/src/strings.bif
index b212ec782b..53c5a94c65 100644
--- a/src/strings.bif
+++ b/src/strings.bif
@@ -1166,8 +1166,8 @@ function hexdump%(data_str: string%) : string
 #define HEX_LINE_RIGHT_MIDDLE        31
 #define HEX_BLOCK_LEN                23
 #define HEX_LINE_BYTES               16
-#define NULL_CHAR                    '.'
-#define NONPRINT_CHAR                '.'
+constexpr char NULL_CHAR = '.';
+constexpr char NONPRINT_CHAR = '.';
 
 	const u_char* data = data_str->Bytes();
 	unsigned data_size = data_str->Len();
@@ -1211,7 +1211,7 @@ function hexdump%(data_str: string%) : string
 		// If unprintable, use special characters:
 		if ( val < 0x20 || val >= 0x7f )
 			{
-			if ( val == 0 )
+			if ( val == 0x00 )
 				ascii_byte = NULL_CHAR;
 			else
 				ascii_byte = NONPRINT_CHAR;