https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110000
Bug ID: 110000
Summary: GCC should implement
exclude_from_explicit_instantiation
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: nikolasklauser at berlin dot de
Target Milestone: ---
`exclude_from_explicit_instantiation` is an attribute implemented by clang. It
tells the compiler that a function should not be part of an explicit
instantiation. This allows libraries to have greater control over which
functions are part of their ABI and which aren't. It is used extensively in
libc++ to keep the ABI surface as small as possible. Currently, libc++ uses
always_inline if exclude_from_explicit_instantiation isn't available, resulting
in almost every function in the library being declared as always_inline.
Replacing always_inline with exclude_from_explicit_instantiation would
approximately halve the time it takes to run the libc++ test suite with GCC.
(removing always_inline brings the time down to about the same as clang takes)
