942383 - NS_PRECONDITION predicates are shown with macros expanded

Status: NEW

(Core :: XPCOM, defect)

Description

[Jesse Ruderman]

I'm now seeing

###!!! ASSERTION: containing block height must be constrained: 'containingBlockHeight != nscoord(1 << 30)', file layout/generic/nsHTMLReflowState.cpp, line 1319

where the code is

NS_PRECONDITION(containingBlockHeight != NS_AUTOHEIGHT, "containing block height must be constrained");

This makes my fuzzer think it's a different assertion than the one it knows about, and it can also be ugly with more complex macros.

All of the assertions where I hit this are NS_PRECONDITION rather than NS_ASSERTION:

http://mxr.mozilla.org/mozilla-central/source/layout/generic/nsHTMLReflowState.cpp#1318
http://mxr.mozilla.org/mozilla-central/source/layout/forms/nsFieldSetFrame.cpp#426
http://mxr.mozilla.org/mozilla-central/source/layout/forms/nsHTMLButtonControlFrame.cpp#174

I think this is a regression from 
http://hg.mozilla.org/mozilla-central/rev/88b2741cd866

Comment 1

[(Away)]

NS_PRECONDITION is now going through an extra layer of #define evaluation.

I *think* you can avoid evaluating by doing:
#define NS_PRECONDITION NS_ASSERTION

Comment 2

[Benjamin Smedberg]

Probably yes. r=me for that change if it does the right thing, Jesse.