From 76e13b586ff690dd3312f719f305c0d1021cd505 Mon Sep 17 00:00:00 2001 From: Lenny Maiorani Date: Sat, 3 Nov 2018 21:15:05 -0600 Subject: [PATCH] warnings: Compiler warning on memset usage for non-trivial type Problem: - IS_TRIVIALLY_CONSTRUCTIBLE macro does not work correctly resulting in `memset()` usage to set a non-trivial type to 0 when `nontrivial_t` is passed in from the tests. - Warning reported by GCC when compiling with `--enable-werror`. Solution: - Use the standard algorithm `std::fill_n()` and let the compiler determine the optimal way of looping or using `memset()`. --- src/prevector.h | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/src/prevector.h b/src/prevector.h index 6ddb6f321..aa7757374 100644 --- a/src/prevector.h +++ b/src/prevector.h @@ -10,6 +10,7 @@ #include #include +#include #include #include #include @@ -198,22 +199,11 @@ private: const T* item_ptr(difference_type pos) const { return is_direct() ? direct_ptr(pos) : indirect_ptr(pos); } void fill(T* dst, ptrdiff_t count) { - if (IS_TRIVIALLY_CONSTRUCTIBLE::value) { - // The most common use of prevector is where T=unsigned char. For - // trivially constructible types, we can use memset() to avoid - // looping. - ::memset(dst, 0, count * sizeof(T)); - } else { - for (auto i = 0; i < count; ++i) { - new(static_cast(dst + i)) T(); - } - } + std::fill_n(dst, count, T{}); } void fill(T* dst, ptrdiff_t count, const T& value) { - for (auto i = 0; i < count; ++i) { - new(static_cast(dst + i)) T(value); - } + std::fill_n(dst, count, value); } template