In file included from /root/firefox-gcc-last/obj-x86_64-pc-linux-gnu/parser/htmlparser/Unified_cpp_parser_htmlparser0.cpp:83:0: /root/firefox-gcc-last/parser/htmlparser/nsScanner.cpp: In constructor 'nsScanner::nsScanner(const nsAString&)': /root/firefox-gcc-last/parser/htmlparser/nsScanner.cpp:60:58: error: 'void* memset(void*, int, size_t)' clearing an object of non-trivial type 'class nsScannerIterator'; use assignment or value-initialization instead [-Werror=class-memaccess] memset(&mCurrentPosition, 0, sizeof(mCurrentPosition));

I think here it's resonable to not have the default constructor of nsScannerIterator, see [1] https://dxr.mozilla.org/mozilla-central/source/parser/htmlparser/nsScannerString.h#343 And by removing [1] nsScannerIterator becomes a trivial class.

Comment on attachment 8922363 [details] Bug 1411615 - make nsScannerIterator a trivial type in order to use memset. https://reviewboard.mozilla.org/r/193412/#review198636

Pushed by bpostelnicu@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/046492264917 make nsScannerIterator a trivial type in order to use memset. r=hsivonen