From f7c922ed3d8e3cb54febbdc594ce9f4400e0d290 Mon Sep 17 00:00:00 2001 From: Murilo Opsfelder Araujo Date: Tue, 15 May 2018 10:49:50 -0300 Subject: HACKING: document preference for g_new instead of g_malloc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch documents the preference for g_new instead of g_malloc. The reasons were adapted from commit b45c03f585ea9bb1af76c73e82195418c294919d. Discussion in QEMU's mailing list: http://lists.nongnu.org/archive/html/qemu-devel/2018-05/msg03238.html Cc: qemu-devel@nongnu.org Cc: David Hildenbrand Cc: Eduardo Habkost Cc: Markus Armbruster Cc: Paolo Bonzini Signed-off-by: Murilo Opsfelder Araujo Reviewed-by: Eric Blake Reviewed-by: Alex Bennée Reviewed-by: David Hildenbrand Signed-off-by: Michael Tokarev --- HACKING | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/HACKING b/HACKING index 4125c97..0fc3e0f 100644 --- a/HACKING +++ b/HACKING @@ -118,6 +118,15 @@ Please note that g_malloc will exit on allocation failure, so there is no need to test for failure (as you would have to with malloc). Calling g_malloc with a zero size is valid and will return NULL. +Prefer g_new(T, n) instead of g_malloc(sizeof(T) * n) for the following +reasons: + + a. It catches multiplication overflowing size_t; + b. It returns T * instead of void *, letting compiler catch more type + errors. + +Declarations like T *v = g_malloc(sizeof(*v)) are acceptable, though. + Memory allocated by qemu_memalign or qemu_blockalign must be freed with qemu_vfree, since breaking this will cause problems on Win32. -- cgit v1.1