From 3dcde736d012a191cca60e5d5dbd80ef971768e0 Mon Sep 17 00:00:00 2001 From: Daniel Cheng Date: Wed, 5 Feb 2025 15:18:48 -0800 Subject: [PATCH] Use __has_attribute to check for __counted_by__ support The initial clang patch to support __counted_by__ was landed and reverted several times. There are some clang toolchains (e.g. the Android toolchain) that report themselves as version 18 but do not support __counted_by__. While it is debatable if Android should be shipping a pre-release clang, using __has_attribute should be a bit simpler overall. Note that this doesn't migrate everything else to use __has_attribute: while clang has always supported __has_attribute, gcc didn't support it until a bit later. --- libxml.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/libxml.h b/libxml.h index 1fb8beb1..f2fcb455 100644 --- a/libxml.h +++ b/libxml.h @@ -29,6 +29,12 @@ #include "config.h" #include +#if defined(__has_attribute) +#define XML_HAS_ATTRIBUTE(x) __has_attribute(x) +#else +#define XML_HAS_ATTRIBUTE(x) 0 +#endif + #if __STDC_VERSION__ >= 199901L #define XML_INLINE inline #elif defined(_MSC_VER) @@ -71,8 +77,7 @@ #define ATTRIBUTE_DESTRUCTOR __attribute__((destructor)) #endif -#if (defined(__clang__) && __clang_major__ >= 18) || \ - (defined(__GNUC__) && __GNUC__ >= 15) +#if XML_HAS_ATTRIBUTE(__counted_by__) #define ATTRIBUTE_COUNTED_BY(c) __attribute__((__counted_by__(c))) #else #define ATTRIBUTE_COUNTED_BY(c)