Merge pull request #4978 from randombit/jack/clang-tidy-misc-redundant-expression

Enable and fix clang-tidy warning misc-redundant-expression

Author: randombit

src/.clang-tidy

@@ -27,7 +27,6 @@ Checks: >
     -cppcoreguidelines-prefer-member-initializer,
     -misc-const-correctness,
     -misc-include-cleaner,
-    -misc-redundant-expression,
     -misc-misplaced-const,
     -misc-confusable-identifiers,
     -modernize-pass-by-value,

src/scripts/dev_tools/run_clang_tidy.py

@@ -58,7 +58,6 @@
     'cppcoreguidelines-prefer-member-initializer',
     'misc-const-correctness', # pretty noisy
     'misc-include-cleaner',
-    'misc-redundant-expression', # BigInt seems to confuse clang-tidy
     'misc-misplaced-const',
     'misc-confusable-identifiers',
     'modernize-pass-by-value',

src/tests/test_ec_group.cpp

@@ -685,7 +685,7 @@ class EC_Point_Arithmetic_Tests final : public Test {
             result.start_timer();
 
             const auto one = Botan::EC_Scalar::one(group);
-            const auto zero = one - one;
+            const auto zero = one - one;  // NOLINT(*-redundant-expression)
             const auto g = Botan::EC_AffinePoint::generator(group);
             const auto g_bytes = g.serialize_uncompressed();
 
@@ -716,7 +716,7 @@ class EC_Point_Arithmetic_Tests final : public Test {
             result.confirm("Scalar::zero is zero", zero.is_zero());
             result.confirm("(zero+zero) is zero", (zero + zero).is_zero());
             result.confirm("(zero*zero) is zero", (zero * zero).is_zero());
-            result.confirm("(zero-zero) is zero", (zero - zero).is_zero());
+            result.confirm("(zero-zero) is zero", (zero - zero).is_zero());  // NOLINT(*-redundant-expression)
 
             const auto neg_zero = zero.negate();
             result.confirm("zero.negate() is zero", neg_zero.is_zero());
@@ -726,7 +726,7 @@ class EC_Point_Arithmetic_Tests final : public Test {
             result.confirm("(nz+zero) is zero", (neg_zero + zero).is_zero());
 
             result.confirm("Scalar::one is not zero", !one.is_zero());
-            result.confirm("(one-one) is zero", (one - one).is_zero());
+            result.confirm("(one-one) is zero", (one - one).is_zero());  // NOLINT(*-redundant-expression)
             result.confirm("(one+one.negate()) is zero", (one + one.negate()).is_zero());
             result.confirm("(one.negate()+one) is zero", (one.negate() + one).is_zero());
 

src/tests/test_ecc_pointmul.cpp

@@ -186,7 +186,7 @@ class ECC_Mul2_Inf_Tests final : public Test {
             const auto neg_r = r.negate();
             const auto neg_r2 = neg_r + neg_r;
 
-            const auto zero = r - r;
+            const auto zero = r - r;  // NOLINT(*-redundant-expression)
             result.confirm("Computed EC_Scalar is zero", zero.is_zero());
 
             const auto g2 = g.add(g);
@@ -280,7 +280,7 @@ class ECC_Scalar_Arithmetic_Tests final : public Test {
                              const Botan::EC_Group& group,
                              Botan::RandomNumberGenerator& rng) const {
          const auto one = Botan::EC_Scalar::one(group);
-         const auto zero = one - one;
+         const auto zero = one - one;  // NOLINT(*-redundant-expression)
          const auto two = one + one;
 
          const size_t order_bytes = group.get_order_bytes();

src/tests/test_ecdh.cpp

@@ -74,7 +74,8 @@ class ECDH_AllGroups_Tests : public Test {
                // Regression test: prohibit loading an all-zero private key
                result.test_throws<Botan::Invalid_Argument>("all-zero private key is unacceptable", [&] {
                   const auto one = Botan::EC_Scalar::one(group);
-                  Botan::ECDH_PrivateKey(group, one - one);
+                  const auto zero = one - one;  // NOLINT(*-redundant-expression)
+                  Botan::ECDH_PrivateKey(group, zero);
                });
 
                // Regression test: prohibit loading a public point that is the identity (point at infinity)

src/tests/test_kyber.cpp

@@ -16,7 +16,6 @@
 #include "test_rng.h"
 #include "tests.h"
 
-#include <cmath>
 #include <iterator>
 #include <memory>
 
@@ -379,6 +378,7 @@ void test_compress_roundtrip(Test::Result& result) {
 
    result.start_timer();
 
+   // NOLINTNEXTLINE(*-redundant-expression)
    for(uint16_t x = 0; x < q && x < (1 << d); ++x) {
       const uint16_t c = Kyber_Algos::compress<d>(Kyber_Algos::decompress<d>(x));
       if(x != c) {