From deefc2d9f6a24a5787598fa70ddfa4a91601f202 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Wed, 8 Dec 2021 17:39:39 -0800 Subject: [PATCH] flex-array: simplify compiler-specific workaround We use "type array[];" syntax for the flex-array member at the end of a struct under C99 or later, except when we are building with older SUNPRO_C compilers. As we find more vendor compilers that claim to grok C99 but not understand the flex-array syntax, the existing "If we are using C99, but not with these compilers..." conditional will keep growing. Make it more manageable by listing vendor-specific exceptions earlier, with the expectation that new exceptions will not be combined into existing ones to make the condition longer, and instead will be implemented as a new "#elif" in the cascade of similar to old SUNPRO_C, we can just add a single line #elif defined(_MSC_VER) immediately before "#elif defined(__GNUC__)" to cause us to fallback to the safer but a bit wasteful version. Signed-off-by: Junio C Hamano --- git-compat-util.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/git-compat-util.h b/git-compat-util.h index d70ce14286..1a0846402f 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -33,14 +33,23 @@ /* * See if our compiler is known to support flexible array members. */ -#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && (!defined(__SUNPRO_C) || (__SUNPRO_C > 0x580)) -# define FLEX_ARRAY /* empty */ + +/* + * Check vendor specific quirks first, before checking the + * __STDC_VERSION__, as vendor compilers can lie and we need to be + * able to work them around. Note that by not defining FLEX_ARRAY + * here, we can fall back to use the "safer but a bit wasteful" one + * later. + */ +#if defined(__SUNPRO_C) && (__SUNPRO_C <= 0x580) #elif defined(__GNUC__) # if (__GNUC__ >= 3) # define FLEX_ARRAY /* empty */ # else # define FLEX_ARRAY 0 /* older GNU extension */ # endif +#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) +# define FLEX_ARRAY /* empty */ #endif /*