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.TH intro 3attr 2025-06-28 "Linux man-pages 6.15"
.SH NAME
intro \- C/C++ attributes
.SH SYNOPSIS
.nf
.BI [[ attr ]]
.BI [[ vendor :: attr ]]
.fi
.SH DESCRIPTION
Attributes modify the properties of a source construct,
such as a type, a variable, or a function.
.P
The standard syntax allows specifying a
.I vendor
for non-standard attributes.
.SH VERSIONS
C and C++ dialects have provided various forms of attributes
before standardization.
.TP
.BI __attribute__(( attr ))
This is the GNU syntax for attributes.
It is supported by both GCC and Clang.
.TP
.BI __declspec( attr )
This is the MSVC syntax for attributes.
It is supported by Clang.
.SH STANDARDS
C23, C++23.
.SH HISTORY
.TP
.BI [[ attr ]]
.TQ
.BI [[ vendor :: attr ]]
C23, C++11.
.TP
.BI [[ attr ]]
.TQ
.BI [[gnu:: attr ]]
gcc 10, g++ 9, clang 9, clang++ 9.
.TP
.BI __attribute__(( attr ))
gcc, g++, clang, clang++.
.TP
.BI __declspec( attr )
clang, clang++.