The Symbian team recommends against using the "release_gcce" flag when building with the GCCE compiler and instead to put the generated code into the "armv5" location (together with the output of the RVCT compiler which is compatible with GCCE).
Not using the release_gcce flags will result in the following issues:
1) The main issue is that qmake generates template pkg files which specify deployment like this:
"/s60/devices/git_symbian3/epoc32/release/$(PLATFORM)/$(TARGET)/qmlphotoviewer.exe" - "!:\sys\bin\qmlphotoviewer.exe".
Fixing this so that specifying QT_SIS_TARGET=release-gcce would look files in armv5/urel instead of gcce/urel would require some ugly hacks to our sis creation and patching scripts, which currently work identically for both symbian-abld and symbian-sbsv2, and in fact are currently not even aware which toolchain is used.
2) Avoid massive warnings about duplicate makefile targets when doing "make clean" or "make export", which add "-c <target>" for all supported builds. For example, having both "-c armv5_urel" and "-c arm.v5.urel.gcce4_4_1" will generate duplicate makefile targets somewhere down the line in raptor toolchain. Since they essentially target same stuff, we could work around this by removing either armv5 or gcce clauses from these targets, so this is not a major issue.
Note: We have http://developer.symbian.org/bugs/show_bug.cgi?id=3553 open to get the gcce_release issue fixed in the symbian build system. If that gets done then the priority of this bug here can probably get lowered.