4 files changed, 19 insertions, 15 deletions
diff --git a/src/util/moneystr.h b/src/util/moneystr.h
index 9133f46d5d..b8e2812a96 100644
--- a/src/util/moneystr.h
+++ b/src/util/moneystr.h
@@ -9,16 +9,17 @@
 #ifndef BITCOIN_UTIL_MONEYSTR_H
 #define BITCOIN_UTIL_MONEYSTR_H
 
-#include <stdint.h>
-#include <string>
-
 #include <amount.h>
+#include <attributes.h>
+
+#include <cstdint>
+#include <string>
 
 /* Do not use these functions to represent or parse monetary amounts to or from
  * JSON but use AmountFromValue and ValueFromAmount for that.
  */
 std::string FormatMoney(const CAmount& n);
-bool ParseMoney(const std::string& str, CAmount& nRet);
-bool ParseMoney(const char* pszIn, CAmount& nRet);
+NODISCARD bool ParseMoney(const std::string& str, CAmount& nRet);
+NODISCARD bool ParseMoney(const char* pszIn, CAmount& nRet);
 
 #endif // BITCOIN_UTIL_MONEYSTR_H
diff --git a/src/util/strencodings.cpp b/src/util/strencodings.cpp
index 2a2df43337..46146be66f 100644
--- a/src/util/strencodings.cpp
+++ b/src/util/strencodings.cpp
@@ -263,7 +263,7 @@ std::string DecodeBase32(const std::string& str)
     return std::string((const char*)vchRet.data(), vchRet.size());
 }
 
-static bool ParsePrechecks(const std::string& str)
+NODISCARD static bool ParsePrechecks(const std::string& str)
 {
     if (str.empty()) // No empty string allowed
         return false;
diff --git a/src/util/strencodings.h b/src/util/strencodings.h
index 87ccf40a1b..7d16d7dcfd 100644
--- a/src/util/strencodings.h
+++ b/src/util/strencodings.h
@@ -9,7 +9,9 @@
 #ifndef BITCOIN_UTIL_STRENCODINGS_H
 #define BITCOIN_UTIL_STRENCODINGS_H
 
-#include <stdint.h>
+#include <attributes.h>
+
+#include <cstdint>
 #include <string>
 #include <vector>
 
@@ -92,35 +94,35 @@ constexpr inline bool IsSpace(char c) noexcept {
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-bool ParseInt32(const std::string& str, int32_t *out);
+NODISCARD bool ParseInt32(const std::string& str, int32_t *out);
 
 /**
  * Convert string to signed 64-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-bool ParseInt64(const std::string& str, int64_t *out);
+NODISCARD bool ParseInt64(const std::string& str, int64_t *out);
 
 /**
  * Convert decimal string to unsigned 32-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-bool ParseUInt32(const std::string& str, uint32_t *out);
+NODISCARD bool ParseUInt32(const std::string& str, uint32_t *out);
 
 /**
  * Convert decimal string to unsigned 64-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-bool ParseUInt64(const std::string& str, uint64_t *out);
+NODISCARD bool ParseUInt64(const std::string& str, uint64_t *out);
 
 /**
  * Convert string to double with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid double,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-bool ParseDouble(const std::string& str, double *out);
+NODISCARD bool ParseDouble(const std::string& str, double *out);
 
 template<typename T>
 std::string HexStr(const T itbegin, const T itend, bool fSpaces=false)
@@ -173,7 +175,7 @@ bool TimingResistantEqual(const T& a, const T& b)
  * @returns true on success, false on error.
  * @note The result must be in the range (-10^18,10^18), otherwise an overflow error will trigger.
  */
-bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out);
+NODISCARD bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out);
 
 /** Convert from one power-of-2 number base to another. */
 template<int frombits, int tobits, bool pad, typename O, typename I>
@@ -200,7 +202,7 @@ bool ConvertBits(const O& outfn, I it, I end) {
 }
 
 /** Parse an HD keypaths like "m/7/0'/2000". */
-bool ParseHDKeypath(const std::string& keypath_str, std::vector<uint32_t>& keypath);
+NODISCARD bool ParseHDKeypath(const std::string& keypath_str, std::vector<uint32_t>& keypath);
 
 /**
  * Converts the given character to its lowercase equivalent.
diff --git a/src/util/system.h b/src/util/system.h
index 5634b8dd61..bebb089a2a 100644
--- a/src/util/system.h
+++ b/src/util/system.h
@@ -14,6 +14,7 @@
 #include <config/bitcoin-config.h>
 #endif
 
+#include <attributes.h>
 #include <compat.h>
 #include <fs.h>
 #include <logging.h>
@@ -159,7 +160,7 @@ public:
      */
     void SelectConfigNetwork(const std::string& network);
 
-    bool ParseParameters(int argc, const char* const argv[], std::string& error);
+    NODISCARD bool ParseParameters(int argc, const char* const argv[], std::string& error);
     bool ReadConfigFiles(std::string& error, bool ignore_invalid_keys = false);
 
     /**