CWG2695 Semantic ignorability of attributes

Author: burblebee

source/declarations.tex

@@ -8511,6 +8511,17 @@
 the rules specifying to which entity or statement the attribute can apply or
 the syntax rules for the attribute's \grammarterm{attribute-argument-clause}, if any.
 \end{note}
+\begin{note}
+The \grammarterm{attribute}{s} specified in \ref{dcl.attr}
+have optional semantics:
+given a well-formed program,
+removing all instances of any one of those \grammarterm{attribute}{s}
+results in a program whose set of possible executions\iref{intro.abstract}
+for a given input is
+a subset of those of the original program for the same input,
+absent implementation-defined guarantees
+with respect to that \grammarterm{attribute}.
+\end{note}
 An \grammarterm{attribute-token} is reserved for future standardization if
 \begin{itemize}
 \item it is not an \grammarterm{attribute-scoped-token} and