695171 - Make our operator new throw bad_alloc

Status: RESOLVED FIXED

(Core :: General, defect)

Description

[Jeff Muizelaar [:jrmuizel]]

Attachment: add throw(std::bad_alloc)

If new doesn't throw bad_alloc the compiler emits a null check after to avoid calling the constructor. http://llvm.org/bugs/show_bug.cgi?id=10895

Adding throw(std::bad_alloc) shaves 57KB of .text off a gcc mac build. I expect it would take more off the clang build.

Comment 1

[(no longer active)]

I'd rename the macros since the names after this patch would just be lies.

Comment 2

[Jeff Muizelaar [:jrmuizel]]

I don't see how they are more lies than before.

Comment 3

[(no longer active)]

As promised to Jeff, I measured how much of a size change this caused with Mac.  The answer is 0.

__TEXT	__DATA	__OBJC	others	dec	hex
24739840	2547712	0	24514560	51802112	3167000	obj-ff-opt/dist/Nightly2.app/Contents/MacOS/XUL
24739840	2547712	0	24514560	51802112	3167000	obj-ff-opt/dist/Nightly.app/Contents/MacOS/XUL

Comment 4

[Jeff Muizelaar [:jrmuizel]]

Fortunately, my results don't match Ehsan's.

/tmp$ size XUL-pre 
__TEXT	__DATA	__OBJC	others	dec	hex
24637440	2539520	0	24469504	51646464	3141000
/tmp$ size XUL-post 
__TEXT	__DATA	__OBJC	others	dec	hex
24576000	2539520	0	24469504	51585024	3132000

Which gives a savings of 61KB

Comment 5

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

https://hg.mozilla.org/mozilla-central/rev/2606bc44cb7c