From: Thomas Munro Date: Mon, 11 Dec 2023 20:31:44 +0000 (+1300) Subject: Define unconstify() and unvolatize() for C++. X-Git-Tag: REL_17_BETA1~1298 X-Git-Url: http://git.postgresql.org/gitweb/?a=commitdiff_plain;h=baf7c93ed583949d837bc13f24a15a0efbcb1ae7;p=postgresql.git Define unconstify() and unvolatize() for C++. These two macros wouldn't work if used in an inline function definition in a header seen by g++, because __builtin_types_compatible_p is only available in C. Redirect to standard C++ const_cast (which also adds/removes volatile despite its name). Per cpluspluscheck failure in a development branch. Suggested-by: Peter Eisentraut Discussion: https://postgr.es/m/CA%2BhUKGK3OXFjkOyZiw-DgL2bUqk9by1uGuCnViJX786W%2BfyDSw%40mail.gmail.com --- diff --git a/src/include/c.h b/src/include/c.h index 82f8e9d4c7b..4b0f5138d83 100644 --- a/src/include/c.h +++ b/src/include/c.h @@ -1245,7 +1245,10 @@ typedef union PGAlignedXLogBlock * Note that this only works in function scope, not for global variables (it'd * be nice, but not trivial, to improve that). */ -#if defined(HAVE__BUILTIN_TYPES_COMPATIBLE_P) +#if defined(__cplusplus) +#define unconstify(underlying_type, expr) const_cast(expr) +#define unvolatize(underlying_type, expr) const_cast(expr) +#elif defined(HAVE__BUILTIN_TYPES_COMPATIBLE_P) #define unconstify(underlying_type, expr) \ (StaticAssertExpr(__builtin_types_compatible_p(__typeof(expr), const underlying_type), \ "wrong cast"), \