Fix initialization in test (#1140)

* Suppress unsafe-buffer-usage

include/gsl/span

@@ -63,6 +63,12 @@
 #pragma GCC diagnostic ignored "-Wsign-conversion"
 #endif
 
+// Turn off clang unsafe buffer warnings as all accessed are guarded by runtime checks
+#if defined(__clang__) && __has_warning("-Wunsafe-buffer-usage")
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunsafe-buffer-usage"
+#endif // defined(__clang__) && __has_warning("-Wunsafe-buffer-usage")
+
 namespace gsl
 {
 
@@ -846,4 +852,8 @@ as_writable_bytes(span<ElementType, Extent> s) noexcept
 #pragma GCC diagnostic pop
 #endif // __GNUC__ > 6
 
+#if defined(__clang__) && __has_warning("-Wunsafe-buffer-usage")
+#pragma clang diagnostic pop
+#endif
+
 #endif // GSL_SPAN_H

include/gsl/util

@@ -40,6 +40,12 @@
 
 #endif // _MSC_VER
 
+// Turn off clang unsafe buffer warnings as all accessed are guarded by runtime checks
+#if defined(__clang__) && __has_warning("-Wunsafe-buffer-usage")
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunsafe-buffer-usage"
+#endif // defined(__clang__) && __has_warning("-Wunsafe-buffer-usage")
+
 #if defined(__cplusplus) && (__cplusplus >= 201703L)
 #define GSL_NODISCARD [[nodiscard]]
 #else
@@ -154,4 +160,8 @@ constexpr auto at(std::span<T, extent> sp, const index i) -> decltype(sp[sp.size
 
 #endif // _MSC_VER
 
+#if defined(__clang__) && __has_warning("-Wunsafe-buffer-usage")
+#pragma clang diagnostic pop
+#endif
+
 #endif // GSL_UTIL_H

tests/CMakeLists.txt

@@ -123,11 +123,6 @@ if(MSVC) # MSVC or simulating MSVC
     if (WARN_RESERVED_ID)
       target_compile_options(gsl_tests_config INTERFACE "-Wno-reserved-identifier")
     endif()
-    check_cxx_compiler_flag("-Wno-unsafe-buffer-usage" WARN_UNSAFE_BUFFER)
-    if (WARN_UNSAFE_BUFFER)
-      # This test uses very greedy heuristics such as "no pointer arithmetic on raw buffer"
-      target_compile_options(gsl_tests_config INTERFACE "-Wno-unsafe-buffer-usage")
-    endif()
 else()
     target_compile_options(gsl_tests_config INTERFACE
         -fno-strict-aliasing
@@ -191,6 +186,11 @@ else()
         >
     )
 endif(MSVC)
+check_cxx_compiler_flag("-Wno-unsafe-buffer-usage" WARN_UNSAFE_BUFFER)
+if (WARN_UNSAFE_BUFFER)
+  # This test uses very greedy heuristics such as "no pointer arithmetic on raw buffer"
+  target_compile_options(gsl_tests_config INTERFACE "-Wno-unsafe-buffer-usage")
+endif()
 
 # for tests to find the gtest header
 target_include_directories(gsl_tests_config SYSTEM INTERFACE
@@ -262,11 +262,6 @@ if(MSVC) # MSVC or simulating MSVC
     if (WARN_RESERVED_ID)
       target_compile_options(gsl_tests_config_noexcept INTERFACE "-Wno-reserved-identifier")
     endif()
-    check_cxx_compiler_flag("-Wno-unsafe-buffer-usage" WARN_UNSAFE_BUFFER)
-    if (WARN_UNSAFE_BUFFER)
-      # This test uses very greedy heuristics such as "no pointer arithmetic on raw buffer"
-      target_compile_options(gsl_tests_config_noexcept INTERFACE "-Wno-unsafe-buffer-usage")
-    endif()
 else()
     target_compile_options(gsl_tests_config_noexcept INTERFACE
         -fno-exceptions
@@ -307,6 +302,11 @@ else()
         >
     )
 endif(MSVC)
+check_cxx_compiler_flag("-Wno-unsafe-buffer-usage" WARN_UNSAFE_BUFFER)
+if (WARN_UNSAFE_BUFFER)
+  # This test uses very greedy heuristics such as "no pointer arithmetic on raw buffer"
+  target_compile_options(gsl_tests_config_noexcept INTERFACE "-Wno-unsafe-buffer-usage")
+endif()
 
 add_executable(gsl_noexcept_tests no_exception_ensure_tests.cpp)
 target_link_libraries(gsl_noexcept_tests

tests/span_tests.cpp

@@ -333,7 +333,7 @@ TEST(span_test, from_array_constructor)
         EXPECT_TRUE(s.data() == std::addressof(arr2d[0]));
     }
 
-    int arr3d[2][3][2] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12};
+    int arr3d[2][3][2] = { { {1, 2}, {3, 4}, {5, 6} }, { {7, 8}, {9, 10}, {11, 12} } };
 
 #ifdef CONFIRM_COMPILATION_ERRORS
     {