all: more clang-tidy cleanups

.clang-tidy

@@ -23,11 +23,13 @@ Checks: >
   clang-analyzer-*,
     -clang-analyzer-optin.performance.Padding,
     -clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling,
+    -clang-analyzer-security.insecureAPI.rand,
     -clang-analyzer-security.insecureAPI.strcpy,
   clang-diagnostic-*,
   performance-*,
     -performance-avoid-endl,
     -performance-enum-size,
+    -performance-no-int-to-ptr,
     -performance-unnecessary-value-param,
 FormatStyle: file
 HeaderFilterRegex: '.*'

CMakeLists.txt

@@ -259,7 +259,7 @@ if(NOT UPX_CONFIG_DISABLE_THREADS)
 endif()
 # make sure that threads are indeed fully supported in C++
 if(Threads_FOUND)
-    foreach(f std_lock_guard.cpp)
+    foreach(f std_lock_guard.cpp types_abi.cpp)
         set(CMAKE_TRY_COMPILE_TARGET_TYPE "EXECUTABLE")
         if(NOT UPX_CONFIG_DISABLE_CXX_STANDARD)
             try_compile(result "${CMAKE_CURRENT_BINARY_DIR}"

misc/cmake/try_compile/types_abi.cpp

@@ -0,0 +1,14 @@
+// Copyright (C) Markus Franz Xaver Johannes Oberhumer
+
+#include <stddef.h>
+
+// check ABI - require proper alignment of fundamental types for use in atomics
+static_assert(alignof(char) == sizeof(char), "");
+static_assert(alignof(short) == sizeof(short), "");
+static_assert(alignof(int) == sizeof(int), "");
+static_assert(alignof(long) == sizeof(long), "");
+static_assert(alignof(ptrdiff_t) == sizeof(ptrdiff_t), "");
+static_assert(alignof(size_t) == sizeof(size_t), "");
+static_assert(alignof(void *) == sizeof(void *), "");
+
+int main() { return 0; }

misc/make/Makefile-extra.mk

@@ -225,7 +225,7 @@ build/analyze/clang-tidy-bzip2/debug build/analyze/clang-tidy-bzip2/release: $$(
 build/analyze/clang-tidy-ucl/debug build/analyze/clang-tidy-ucl/release: $$(CLANG_TIDY_BUILD_BASE)/$$(notdir $$@) PHONY
 	$(RUN_CLANG_TIDY_WERROR) -config-file ./misc/analyze/clang-tidy/clang-tidy-ucl.yml   /vendor/ucl/
 build/analyze/clang-tidy-zlib/debug build/analyze/clang-tidy-zlib/release: $$(CLANG_TIDY_BUILD_BASE)/$$(notdir $$@) PHONY
-	$(RUN_CLANG_TIDY_WERROR) -config-file ./misc/analyze/clang-tidy/clang-tidy-zlib.yml  /vendor/zlib/
+	$(RUN_CLANG_TIDY)        -config-file ./misc/analyze/clang-tidy/clang-tidy-zlib.yml  /vendor/zlib/
 build/analyze/clang-tidy-zstd/debug build/analyze/clang-tidy-zstd/release: $$(CLANG_TIDY_BUILD_BASE)/$$(notdir $$@) PHONY
 	$(RUN_CLANG_TIDY)        -config-file ./misc/analyze/clang-tidy/clang-tidy-zstd.yml  /vendor/zstd/
 build/analyze/clang-tidy/debug build/analyze/clang-tidy/release: build/analyze/clang-tidy-upx/$$(notdir $$@)

src/check/dt_cxxlib.cpp

@@ -257,35 +257,44 @@ TEST_CASE("upx::ptr_std_atomic_cast") {
     (void) upx::ptr_std_atomic_cast((upx_int32_t *) nullptr);
     (void) upx::ptr_std_atomic_cast((int *) nullptr);
     (void) upx::ptr_std_atomic_cast((long *) nullptr);
+    (void) upx::ptr_std_atomic_cast((ptrdiff_t *) nullptr);
     (void) upx::ptr_std_atomic_cast((size_t *) nullptr);
     (void) upx::ptr_std_atomic_cast((void **) nullptr);
 }
 #endif
 
 TEST_CASE("upx::atomic_exchange") {
+#if defined(__riscv)
+// RISC-V has no support for subword atomic operations and needs libatomic to emulate
+#else
     {
         upx_int8_t x = -1;
         upx_int8_t y = upx::atomic_exchange(&x, (upx_int8_t) 2);
         CHECK_EQ(x, 2);
         CHECK_EQ(y, -1);
+        UNUSED(y);
     }
     {
         upx_int16_t x = -1;
         upx_int16_t y = upx::atomic_exchange(&x, (upx_int16_t) 2);
         CHECK_EQ(x, 2);
         CHECK_EQ(y, -1);
+        UNUSED(y);
     }
     {
         upx_int32_t x = -1;
         upx_int32_t y = upx::atomic_exchange(&x, (upx_int32_t) 2);
         CHECK_EQ(x, 2);
         CHECK_EQ(y, -1);
+        UNUSED(y);
     }
+#endif // __riscv
     {
         size_t x = (size_t) 0 - 1;
         size_t y = upx::atomic_exchange(&x, (size_t) 2);
         CHECK_EQ(x, 2);
         CHECK_EQ(y, (size_t) 0 - 1);
+        UNUSED(y);
     }
     {
         const int buf[2] = {101, 202};
@@ -297,6 +306,7 @@ TEST_CASE("upx::atomic_exchange") {
         p = upx::atomic_exchange(&ptr_array[1], p);
         CHECK_EQ(p, buf + 1);
         assert_noexcept(*ptr_array[0] == 202 && *ptr_array[1] == 101);
+        UNUSED(p);
     }
 }
 

src/util/cxxlib.h

@@ -206,16 +206,20 @@ template <class T>
 forceinline T atomic_exchange(T *ptr, T new_value) noexcept {
     static_assert(std::is_standard_layout_v<T>);
     static_assert(std::is_trivially_copyable_v<T>);
+#if !(WITH_THREADS)
+    T old_value = *ptr;
+    *ptr = new_value;
+    return old_value;
+#else
+    static_assert(sizeof(T) <= sizeof(void *)); // UPX convention: restrict to fundamental types
+    static_assert(alignof(T) == sizeof(T));     // UPX convention: require proper alignment
 #if __has_builtin(__atomic_exchange_n) && defined(__ATOMIC_SEQ_CST)
     return __atomic_exchange_n(ptr, new_value, __ATOMIC_SEQ_CST);
 #elif __has_builtin(__sync_swap)
     return __sync_swap(ptr, new_value);
-#elif WITH_THREADS
-    return std::atomic_exchange(ptr_std_atomic_cast(ptr), new_value);
 #else
-    T old_value = *ptr;
-    *ptr = new_value;
-    return old_value;
+    return std::atomic_exchange(ptr_std_atomic_cast(ptr), new_value);
+#endif
 #endif
 }