From b79ce6e1aa40172750b1b6906e2b0437d2fdfec8 Mon Sep 17 00:00:00 2001 From: Nathan Sidwell Date: Thu, 17 Dec 2020 10:28:18 -0800 Subject: [PATCH] doc: Standard library header units It seems users are confused by the lack of standard library header units. gcc/ * doc/invoke.texi (C++ Modules): Document lack of std library header units. --- gcc/doc/invoke.texi | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 054b8371593..8766bcdfc18 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -32891,6 +32891,13 @@ the purview of a named module. This is not implemented. Such declarations will be attached to the module, if any, in which they are declared. +@item Standard Library Header Units +The Standard Library is not provided as importable header units. If +you want to import such units, you must explicitly build them first. +If you do not do this with care, you may have multiple declarations, +which the module machinery must merge---compiler resource usage can be +affected by how you partition header files into header units. + @end table Modular compilation is @emph{not} enabled with just the -- 2.30.2