75951 2012-01-10 03:51:48 -0800 [Qt] DRT crashes with Qt 5 2012-01-10 04:12:43 -0800 1 1 1 Unclassified WebKit New Bugs 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 hausmann hausmann kbalazs ossy webkit.review.bot oldest_to_newest 532951 0 hausmann 2012-01-10 03:51:48 -0800 Various layout tests crash with the DRT and Qt 5 due to a subtle font-config issue. The backtraces indicate that an empty font-family causes crashes with atomic string. The root cause is the fact that the default font family returned by Qt is an empty string, which is not a valid situation. In Qt 4.8 the default font / family was "Helvetica". In Qt 5 the default is queried from font-config by doing the programmatic equivalent of running "fc-match" on the commandline, in src/platformsupport/fontdatabases/fontconfig/qfontconfigdatabase.cpp. You can verify this by calling 'ltrace fc-match' and comparing the font-config commands to what's being done in QFontconfigDatabase::resolveFontFamilyAlias. In a normal "Linux" system the default is defined through a rule like this (from /etc/fonts/conf.d/49-sansserif.conf) : <!-- If the font still has no generic name, add sans-serif --> <match target="pattern"> <test qual="all" name="family" compare="not_eq"> <string>sans-serif</string> </test> <test qual="all" name="family" compare="not_eq"> <string>serif</string> </test> <test qual="all" name="family" compare="not_eq"> <string>monospace</string> </test> <edit name="family" mode="append_last"> <string>sans-serif</string> </edit> </match> This ensures the "last resort fallback", and indeed this is missing in _our_ fonts.conf in Tools/DumpRenderTree/qt/fonts.conf. 532953 1 121825 hausmann 2012-01-10 03:54:57 -0800 Created attachment 121825 Patch 532956 2 121825 ossy 2012-01-10 04:02:36 -0800 Comment on attachment 121825 Patch LGTM,r=me. 532959 3 hausmann 2012-01-10 04:12:04 -0800 Committed r104551: <http://trac.webkit.org/changeset/104551> 532960 4 121825 hausmann 2012-01-10 04:12:43 -0800 Comment on attachment 121825 Patch oops, landed manually 121825 2012-01-10 03:54:57 -0800 2012-01-10 04:12:43 -0800 Patch bug-75951-20120110125507.patch text/plain 1533 hausmann U3VidmVyc2lvbiBSZXZpc2lvbjogMTA0NDU3CmRpZmYgLS1naXQgYS9Ub29scy9DaGFuZ2VMb2cg Yi9Ub29scy9DaGFuZ2VMb2cKaW5kZXggMWVjYjZkZmViOTAxZjI1NTE4YWQ0Y2ZkMzVlZTRhODFi MDdkOWE0ZS4uMTAwMjFiNWU0NzIwYmM4NjI3MjQ4NWRmZWYxM2M3YTkxYjM4Y2NiMiAxMDA2NDQK LS0tIGEvVG9vbHMvQ2hhbmdlTG9nCisrKyBiL1Rvb2xzL0NoYW5nZUxvZwpAQCAtMSwzICsxLDEz IEBACisyMDEyLTAxLTEwICBTaW1vbiBIYXVzbWFubiAgPHNpbW9uLmhhdXNtYW5uQG5va2lhLmNv bT4KKworICAgICAgICBbUXRdIERSVCBjcmFzaGVzIHdpdGggUXQgNQorICAgICAgICBodHRwczov L2J1Z3Mud2Via2l0Lm9yZy9zaG93X2J1Zy5jZ2k/aWQ9NzU5NTEKKworICAgICAgICBSZXZpZXdl ZCBieSBOT0JPRFkgKE9PUFMhKS4KKworICAgICAgICAqIER1bXBSZW5kZXJUcmVlL3F0L2ZvbnRz LmNvbmY6IEFkZCBtaXNzaW5nIGxhc3QtcmVzb3J0IGZvbnQgZmFsbGJhY2sgZm9yIFF0IDUgd2hl cmUKKyAgICAgICAgUXQgcmVsaWVzIG9uIGZvbnQtY29uZmlnIHRvIGRlZmluZSB0aGUgZGVmYXVs dCBmb250IGZhbWlseS4KKwogMjAxMi0wMS0wOSAgQWxleGFuZGVyIEbDpnLDuHkgIDxhaGZAMHg5 MC5kaz4KIAogICAgICAgICBbUXRdIEFkZCBzdXBwb3J0IGZvciBkeW5hbWljYWxseSBlbmFibGlu ZyBhbmQgZGlzYWJsaW5nIHRvdWNoIG1vY2tpbmcgaW4gdGhlIFF0IE1pbmlCcm93c2VyCmRpZmYg LS1naXQgYS9Ub29scy9EdW1wUmVuZGVyVHJlZS9xdC9mb250cy5jb25mIGIvVG9vbHMvRHVtcFJl bmRlclRyZWUvcXQvZm9udHMuY29uZgppbmRleCAzNTQwYzQ3OWY5OTU5ZDllYzFmYzNkZmM2OTE0 ZDAzOGY4ZDUyNjE4Li4wOTUwN2Q0MjViZGQzZTM3NjZkYjRmZjY1NzI2MjljYTU4YjMzODFmIDEw MDY0NAotLS0gYS9Ub29scy9EdW1wUmVuZGVyVHJlZS9xdC9mb250cy5jb25mCisrKyBiL1Rvb2xz L0R1bXBSZW5kZXJUcmVlL3F0L2ZvbnRzLmNvbmYKQEAgLTM4LDYgKzM4LDIzIEBACiAJCTwvZWRp dD4KIAk8L21hdGNoPgogCis8IS0tCisgIElmIHRoZSBmb250IHN0aWxsIGhhcyBubyBnZW5lcmlj IG5hbWUsIGFkZCBzYW5zLXNlcmlmCisgLS0+CisJPG1hdGNoIHRhcmdldD0icGF0dGVybiI+CisJ CTx0ZXN0IHF1YWw9ImFsbCIgbmFtZT0iZmFtaWx5IiBjb21wYXJlPSJub3RfZXEiPgorCQkJPHN0 cmluZz5zYW5zLXNlcmlmPC9zdHJpbmc+CisJCTwvdGVzdD4KKwkJPHRlc3QgcXVhbD0iYWxsIiBu YW1lPSJmYW1pbHkiIGNvbXBhcmU9Im5vdF9lcSI+CisJCQk8c3RyaW5nPnNlcmlmPC9zdHJpbmc+ CisJCTwvdGVzdD4KKwkJPHRlc3QgcXVhbD0iYWxsIiBuYW1lPSJmYW1pbHkiIGNvbXBhcmU9Im5v dF9lcSI+CisJCQk8c3RyaW5nPm1vbm9zcGFjZTwvc3RyaW5nPgorCQk8L3Rlc3Q+CisJCTxlZGl0 IG5hbWU9ImZhbWlseSIgbW9kZT0iYXBwZW5kX2xhc3QiPgorCQkJPHN0cmluZz5zYW5zLXNlcmlm PC9zdHJpbmc+CisJCTwvZWRpdD4KKwk8L21hdGNoPgogCiAJPGNvbmZpZz4KIDwhLS0K