qtwebkit creates ARMv5 assembler

Copying from original bug report [obr]:

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Checking the end of the builddlog[1]:

/tmp/ccaKPWJK.s: Assembler messages:
/tmp/ccaKPWJK.s:23: Error: selected processor does not support ARM mode
`blx r0'
make[4]: *** [.obj/jit/JITStubs.o] Error 1

blx is not supported on ARMv4t, lowest arch supported on debian/armel.
One needs to replace this code with:

mov lr,pc
bx r0

Or, alternatively build with -march=armv5. This option would mean than
qtwebkit would be unusable on armv4t hardware. The main usecase for such
hardware is the openmoko freerunner. Do we still have openmoko users who
are interested in qtwebkit?

Riku

[1] <https://buildd.debian.org/status/fetch.php?pkg=qtwebkit-opensource-src&arch=armel&ver=5.2.1%2Bdfsg-3&stamp=1393519544>

[obr] <https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=740334>

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Now what I don't know is if that comes from webkit code itself or has something to do with Qt's core. If it's webkit then we need a fix. In the later case, maybe waiting for 5.3 which will use gcc atomics (supossing this comes from atomics) could solve the issue.