From 0fa7617d84da8b809b14e1e2ee67474526c62021 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Mon, 20 Apr 2020 11:45:06 -0600 Subject: Mark move constructors as "noexcept" I recently learned that move constructors generally should be marked "noexcept". This ensures that standard containers will move objects when possible, rather than copy them. This patch fixes the cases I could find. Note that implicitly-defined or defaulted move constructors will automatically do what you'd expect; that is, they are noexcept if all the members have noexcept move constructors. While doing this, I noticed a couple of odd cases where the move constructor seemed to assume that the object being constructed could have state requiring destruction. I've fixed these as well. See completion_result and scoped_mmap. gdb/ChangeLog 2020-04-20 Tom Tromey * python/python.c (struct gdbpy_event): Mark move constructor as noexcept. * python/py-tui.c (class gdbpy_tui_window_maker): Mark move constructor as noexcept. * completer.h (struct completion_result): Mark move constructor as noexcept. * completer.c (completion_result::completion_result): Use initialization style. Don't call reset_match_list. gdbsupport/ChangeLog 2020-04-20 Tom Tromey * scoped_mmap.h (scoped_mmap): Mark move constructor as noexcept. Use initialization style. Don't call destroy. * scoped_fd.h (class scoped_fd): Mark move constructor as noexcept. * gdb_ref_ptr.h (class ref_ptr): Mark move constructor as noexcept. --- gdbsupport/ChangeLog | 9 +++++++++ gdbsupport/gdb_ref_ptr.h | 2 +- gdbsupport/scoped_fd.h | 2 +- gdbsupport/scoped_mmap.h | 9 +++------ 4 files changed, 14 insertions(+), 8 deletions(-) (limited to 'gdbsupport') diff --git a/gdbsupport/ChangeLog b/gdbsupport/ChangeLog index cd7033d..78fbbe6 100644 --- a/gdbsupport/ChangeLog +++ b/gdbsupport/ChangeLog @@ -1,3 +1,12 @@ +2020-04-20 Tom Tromey + + * scoped_mmap.h (scoped_mmap): Mark move constructor as noexcept. + Use initialization style. Don't call destroy. + * scoped_fd.h (class scoped_fd): Mark move constructor as + noexcept. + * gdb_ref_ptr.h (class ref_ptr): Mark move constructor as + noexcept. + 2020-04-13 Tom Tromey * event-loop.c: Move comment. Remove obsolete comment. diff --git a/gdbsupport/gdb_ref_ptr.h b/gdbsupport/gdb_ref_ptr.h index c5ef13f..de387f5 100644 --- a/gdbsupport/gdb_ref_ptr.h +++ b/gdbsupport/gdb_ref_ptr.h @@ -78,7 +78,7 @@ class ref_ptr } /* Transfer ownership from OTHER. */ - ref_ptr (ref_ptr &&other) + ref_ptr (ref_ptr &&other) noexcept : m_obj (other.m_obj) { other.m_obj = NULL; diff --git a/gdbsupport/scoped_fd.h b/gdbsupport/scoped_fd.h index f40ce8b..ec654df 100644 --- a/gdbsupport/scoped_fd.h +++ b/gdbsupport/scoped_fd.h @@ -30,7 +30,7 @@ class scoped_fd public: explicit scoped_fd (int fd = -1) noexcept : m_fd (fd) {} - scoped_fd (scoped_fd &&other) + scoped_fd (scoped_fd &&other) noexcept : m_fd (other.m_fd) { other.m_fd = -1; diff --git a/gdbsupport/scoped_mmap.h b/gdbsupport/scoped_mmap.h index bab988f..9b74383 100644 --- a/gdbsupport/scoped_mmap.h +++ b/gdbsupport/scoped_mmap.h @@ -42,13 +42,10 @@ public: destroy (); } - scoped_mmap (scoped_mmap &&rhs) + scoped_mmap (scoped_mmap &&rhs) noexcept + : m_mem (rhs.m_mem), + m_length (rhs.m_length) { - destroy (); - - m_mem = rhs.m_mem; - m_length = rhs.m_length; - rhs.m_mem = MAP_FAILED; rhs.m_length = 0; } -- cgit v1.1