As I know, assertions have no effect when Release configuration is selected.
You can just build the JuceDemo project using the Release configuration and see that it crashes when you select “Look-and-feel->Use native window title bar” menu item.
And I’m sure, it’s a crash. Here is the log.
11-05 18:32:15.330: I/InputReader(2300): Touch event's action is 0x1 (deviceType=0) [pCnt=1, s=]
11-05 18:32:15.330: I/InputDispatcher(2300): Delivering touch to current input target: action: 0x1
11-05 18:32:15.330: I/InputDispatcher(2300): Delivering touch to current input target: action: 0x1
11-05 18:32:15.330: I/InputDispatcher(2300): Delivering touch to current input target: action: 0x1
11-05 18:32:15.330: I/InputDispatcher(2300): Delivering touch to current input target: action: 0x1
11-05 18:32:15.440: D/GestureDetector(7822): [Surface Touch Event] mSweepDown False, mLRSDCnt : -1 mTouchCnt : 3 mFalseSizeCnt:0
11-05 18:32:15.575: A/libc(7822): Fatal signal 11 (SIGSEGV) at 0x00000000 (code=1), thread 7822 (com.juce)
11-05 18:32:15.675: I/DEBUG(1918): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
11-05 18:32:15.675: I/DEBUG(1918): Build fingerprint: 'samsung/t03gxx/t03g:4.1.1/JRO03C/N7100XXALJ3:user/release-keys'
11-05 18:32:15.675: I/DEBUG(1918): pid: 7822, tid: 7822, name: com.juce >>> com.juce <<<
11-05 18:32:15.675: I/DEBUG(1918): signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 00000000
11-05 18:32:15.825: I/DEBUG(1918): r0 00000000 r1 40dfa498 r2 00000005 r3 408f2c98
11-05 18:32:15.825: I/DEBUG(1918): r4 bed3f254 r5 00000000 r6 570c9cb8 r7 00000001
11-05 18:32:15.825: I/DEBUG(1918): r8 408d8ec5 r9 00000000 sl bed3f2a0 fp bed3f304
11-05 18:32:15.825: I/DEBUG(1918): ip 408f2ebc sp bed3f228 lr 40886893 pc 40886896 cpsr 60000030
11-05 18:32:15.825: I/DEBUG(1918): d0 000000c843480000 d1 0000000043480000
11-05 18:32:15.825: I/DEBUG(1918): d2 0000000000000000 d3 44a0000000000000
11-05 18:32:15.825: I/DEBUG(1918): d4 0000003200000000 d5 44a0000044340000
11-05 18:32:15.825: I/DEBUG(1918): d6 449fe0004433c000 d7 0000000000000000
11-05 18:32:15.825: I/DEBUG(1918): d8 0000000000000000 d9 0000000000000000
11-05 18:32:15.825: I/DEBUG(1918): d10 0000000000000000 d11 0000000000000000
11-05 18:32:15.825: I/DEBUG(1918): d12 0000000000000000 d13 0000000000000000
11-05 18:32:15.825: I/DEBUG(1918): d14 0000000000000000 d15 0000000000000000
11-05 18:32:15.825: I/DEBUG(1918): d16 4024000000000000 d17 4024000000000000
11-05 18:32:15.825: I/DEBUG(1918): d18 00000000027f8000 d19 2000000840070480
11-05 18:32:15.825: I/DEBUG(1918): d20 ffffffffffffffff d21 ffffffffffffffff
11-05 18:32:15.825: I/DEBUG(1918): d22 ffffffffffffffff d23 ffffffffffffffff
11-05 18:32:15.825: I/DEBUG(1918): d24 ffffffffffffffff d25 ffffffffffffffff
11-05 18:32:15.825: I/DEBUG(1918): d26 ffffffffffffffff d27 ffffffffffffffff
11-05 18:32:15.825: I/DEBUG(1918): d28 ffffffffffffffff d29 ffffffffffffffff
11-05 18:32:15.825: I/DEBUG(1918): d30 ffffffffffffffff d31 ffffffffffffffff
11-05 18:32:15.825: I/DEBUG(1918): scr 60000011
11-05 18:32:15.825: I/DEBUG(1918): backtrace:
11-05 18:32:15.825: I/DEBUG(1918): #00 pc 00039896 /system/lib/libdvm.so
11-05 18:32:15.825: I/DEBUG(1918): #01 pc 00040d4f /system/lib/libdvm.so
11-05 18:32:15.825: I/DEBUG(1918): #02 pc 0028b2e8 /data/data/com.juce/lib/libjuce_jni.so (juce::GlobalRef::callBooleanMethod(_jmethodID*, ...) const+44)
11-05 18:32:15.825: I/DEBUG(1918): #03 pc 00376bb0 /data/data/com.juce/lib/libjuce_jni.so (juce::Component::takeKeyboardFocus(juce::Component::FocusChangeType)+68)
11-05 18:32:15.825: I/DEBUG(1918): stack:
11-05 18:32:15.825: I/DEBUG(1918): bed3f1e8 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f1ec 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f1f0 000003e8
11-05 18:32:15.825: I/DEBUG(1918): bed3f1f4 00000008
11-05 18:32:15.825: I/DEBUG(1918): bed3f1f8 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f1fc 5ce29064 /dev/binder
11-05 18:32:15.825: I/DEBUG(1918): bed3f200 5ce2906c /dev/binder
11-05 18:32:15.825: I/DEBUG(1918): bed3f204 31945112
11-05 18:32:15.825: I/DEBUG(1918): bed3f208 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f20c 516d76d0
11-05 18:32:15.825: I/DEBUG(1918): bed3f210 516d7a50
11-05 18:32:15.825: I/DEBUG(1918): bed3f214 31945112
11-05 18:32:15.825: I/DEBUG(1918): bed3f218 bed3f254 [stack]
11-05 18:32:15.825: I/DEBUG(1918): bed3f21c 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f220 df0027ad
11-05 18:32:15.825: I/DEBUG(1918): bed3f224 00000000
11-05 18:32:15.825: I/DEBUG(1918): #00 bed3f228 bed3f254 [stack]
11-05 18:32:15.825: I/DEBUG(1918): bed3f22c 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f230 570c9cb8 /dev/ashmem/dalvik-LinearAlloc (deleted)
11-05 18:32:15.825: I/DEBUG(1918): bed3f234 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f238 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f23c 570c9cb8 /dev/ashmem/dalvik-LinearAlloc (deleted)
11-05 18:32:15.825: I/DEBUG(1918): bed3f240 40d81068
11-05 18:32:15.825: I/DEBUG(1918): bed3f244 4088dd53 /system/lib/libdvm.so
11-05 18:32:15.825: I/DEBUG(1918): #01 bed3f248 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f24c 570c9cb8 /dev/ashmem/dalvik-LinearAlloc (deleted)
11-05 18:32:15.825: I/DEBUG(1918): bed3f250 40d81068
11-05 18:32:15.825: I/DEBUG(1918): bed3f254 40d81068
11-05 18:32:15.825: I/DEBUG(1918): bed3f258 408ed9e5 /system/lib/libdvm.so
11-05 18:32:15.825: I/DEBUG(1918): bed3f25c 00000000
11-05 18:32:15.825: I/DEBUG(1918): bed3f260 00000001
11-05 18:32:15.825: I/DEBUG(1918): bed3f264 9e29f697
11-05 18:32:15.825: I/DEBUG(1918): bed3f268 587ff5dc
11-05 18:32:15.825: I/DEBUG(1918): bed3f26c 587ff5a8
11-05 18:32:15.825: I/DEBUG(1918): bed3f270 5d794318
11-05 18:32:15.825: I/DEBUG(1918): bed3f274 00000002
11-05 18:32:15.825: I/DEBUG(1918): bed3f278 00000001
11-05 18:32:15.825: I/DEBUG(1918): bed3f27c 56f88bfc
11-05 18:32:15.825: I/DEBUG(1918): bed3f280 40ca59b0
11-05 18:32:15.825: I/DEBUG(1918): bed3f284 5d3b22ec /data/data/com.juce/lib/libjuce_jni.so (juce::GlobalRef::callBooleanMethod(_jmethodID*, ...) const+48)
11-05 18:32:15.825: I/DEBUG(1918): #02 bed3f288 587ff5dc
11-05 18:32:15.825: I/DEBUG(1918): bed3f28c bed3f2a0 [stack]
11-05 18:32:15.825: I/DEBUG(1918): bed3f290 587ff4fc
11-05 18:32:15.825: I/DEBUG(1918): bed3f294 587ff840
11-05 18:32:15.825: I/DEBUG(1918): bed3f298 5d49dbb4 /data/data/com.juce/lib/libjuce_jni.so (juce::Component::takeKeyboardFocus(juce::Component::FocusChangeType)+72)
11-05 18:32:15.825: I/DEBUG(1918): bed3f29c 570c9cb8 /dev/ashmem/dalvik-LinearAlloc (deleted)
11-05 18:32:15.825: I/DEBUG(1918): bed3f2a0 587ff4fc
11-05 18:32:15.825: I/DEBUG(1918): bed3f2a4 5d7940b8
11-05 18:32:15.830: I/DEBUG(1918): memory near r1:
11-05 18:32:15.830: I/DEBUG(1918): 40dfa478 40dfa3d8 592ca0a8 592ff3b8 0000001a ...@..,Y../Y....
11-05 18:32:15.830: I/DEBUG(1918): 40dfa488 40e22868 00000000 00000000 00001a2b h(.@........+...
11-05 18:32:15.830: I/DEBUG(1918): 40dfa498 40dd31e8 00000000 00000000 00000000 .1.@............
11-05 18:32:15.830: I/DEBUG(1918): 40dfa4a8 00000000 00000000 592eb1f3 00000000 ...........Y....
11-05 18:32:15.830: I/DEBUG(1918): 40dfa4b8 00020001 50000184 40cc9000 00000007 .......P...@....
11-05 18:32:15.830: I/DEBUG(1918): memory near r3:
11-05 18:32:15.830: I/DEBUG(1918): 408f2c78 40874dfc 40874e88 40874efc 40874f38 .M.@.N.@.N.@8O.@
11-05 18:32:15.830: I/DEBUG(1918): 408f2c88 4089f061 408a19b5 408b826d 408b4651 a..@...@m..@QF.@
11-05 18:32:15.830: I/DEBUG(1918): 408f2c98 00000000 00000000 00000000 40106111 .............a.@
11-05 18:32:15.830: I/DEBUG(1918): 408f2ca8 400f9828 400f8f24 400f8a98 400f8b74 (..@$..@...@t..@
11-05 18:32:15.830: I/DEBUG(1918): 408f2cb8 400f9c84 400938dc 40093538 400a09f4 ...@.8.@85.@...@
11-05 18:32:15.830: I/DEBUG(1918): memory near r4:
11-05 18:32:15.830: I/DEBUG(1918): bed3f234 00000000 00000000 570c9cb8 40d81068 ...........Wh..@
11-05 18:32:15.830: I/DEBUG(1918): bed3f244 4088dd53 00000000 570c9cb8 40d81068 S..@.......Wh..@
11-05 18:32:15.830: I/DEBUG(1918): bed3f254 40d81068 408ed9e5 00000000 00000001 h..@...@........
11-05 18:32:15.830: I/DEBUG(1918): bed3f264 9e29f697 587ff5dc 587ff5a8 5d794318 ..)....X...X.Cy]
11-05 18:32:15.830: I/DEBUG(1918): bed3f274 00000002 00000001 56f88bfc 40ca59b0 ...........V.Y.@
11-05 18:32:15.830: I/DEBUG(1918): memory near r6:
11-05 18:32:15.830: I/DEBUG(1918): 570c9c98 000011fb 5934f4df 58f2ef18 00000000 ......4Y...X....
11-05 18:32:15.830: I/DEBUG(1918): 570c9ca8 00000000 00000000 40081cc8 00000000 ...........@....
11-05 18:32:15.830: I/DEBUG(1918): 570c9cb8 40dfa498 00000011 0002019f 00010002 ...@............
11-05 18:32:15.830: I/DEBUG(1918): 570c9cc8 593ff0d1 40d82928 000021a7 59359171 ..?Y().@.!..q.5Y
11-05 18:32:15.830: I/DEBUG(1918): 570c9cd8 58f2ef3c 00000000 00000000 00000000 <..X............
11-05 18:32:15.830: I/DEBUG(1918): memory near r8:
11-05 18:32:15.830: I/DEBUG(1918): 408d8ea4 00436663 42666345 66634500 6345005a cfC.EcfB.EcfZ.Ec
11-05 18:32:15.830: I/DEBUG(1918): 408d8eb4 45004c66 44006663 53004600 42004300 fL.Ecf.D.F.S.C.B
11-05 18:32:15.830: I/DEBUG(1918): 408d8ec4 45005a00 00757563 63450066 6d002e6d .Z.Ecuu.f.Ecm..m
11-05 18:32:15.830: I/DEBUG(1918): 408d8ed4 664c4500 4c450044 45004666 004a664c .ELfD.ELfF.ELfJ.
11-05 18:32:15.830: I/DEBUG(1918): 408d8ee4 49664c45 664c4500 4c450053 45004366 ELfI.ELfS.ELfC.E
11-05 18:32:15.830: I/DEBUG(1918): memory near sl:
11-05 18:32:15.830: I/DEBUG(1918): bed3f280 40ca59b0 5d3b22ec 587ff5dc bed3f2a0 .Y.@.";]...X....
11-05 18:32:15.830: I/DEBUG(1918): bed3f290 587ff4fc 587ff840 5d49dbb4 570c9cb8 ...X@..X..I]...W
11-05 18:32:15.830: I/DEBUG(1918): bed3f2a0 587ff4fc 5d7940b8 587ff4f8 00000002 ...X.@y]...X....
11-05 18:32:15.830: I/DEBUG(1918): bed3f2b0 00000001 587ff840 40ca59a0 00000002 ....@..X.Y.@....
11-05 18:32:15.830: I/DEBUG(1918): bed3f2c0 56f88c08 5d49dcac 587ff840 00000002 ...V..I]@..X....
11-05 18:32:15.830: I/DEBUG(1918): memory near fp:
11-05 18:32:15.830: I/DEBUG(1918): bed3f2e4 4086ae74 00000001 40895a43 56f88bf8 t..@....CZ.@...V
11-05 18:32:15.830: I/DEBUG(1918): bed3f2f4 00000001 41e5c860 00000000 00000001 ....`..A........
11-05 18:32:15.830: I/DEBUG(1918): bed3f304 4089a0c7 56f88bf8 5881dde7 5d49e184 ...@...V...X..I]
11-05 18:32:15.830: I/DEBUG(1918): bed3f314 40ca59b0 00000000 00000000 4022a307 .Y.@.........."@
11-05 18:32:15.830: I/DEBUG(1918): bed3f324 4013aa6c 40e0cb28 5881b590 56f88cd4 l..@(..@...X...V
11-05 18:32:15.830: I/DEBUG(1918): memory near ip:
11-05 18:32:15.830: I/DEBUG(1918): 408f2e9c 400f7314 400fd224 400fbbb0 400fd478 .s.@$..@...@x..@
11-05 18:32:15.830: I/DEBUG(1918): 408f2eac 40104e39 400fbef4 400f664c 400fd024 9N.@...@Lf.@$..@
11-05 18:32:15.830: I/DEBUG(1918): 408f2ebc 400fd2d0 400fd0f4 4010380d 400c1971 ...@...@.8.@q..@
11-05 18:32:15.830: I/DEBUG(1918): 408f2ecc 400c1b0d 400f67c0 400fbc9c 400fbce4 ...@.g.@...@...@
11-05 18:32:15.830: I/DEBUG(1918): 408f2edc 401039fd 40103a81 40103ae9 4010422b .9.@.:.@.:.@+B.@
11-05 18:32:15.830: I/DEBUG(1918): memory near sp:
11-05 18:32:15.830: I/DEBUG(1918): bed3f208 00000000 516d76d0 516d7a50 31945112 .....vmQPzmQ.Q.1
11-05 18:32:15.830: I/DEBUG(1918): bed3f218 bed3f254 00000000 df0027ad 00000000 T........'......
11-05 18:32:15.830: I/DEBUG(1918): bed3f228 bed3f254 00000000 570c9cb8 00000000 T..........W....
11-05 18:32:15.830: I/DEBUG(1918): bed3f238 00000000 570c9cb8 40d81068 4088dd53 .......Wh..@S..@
11-05 18:32:15.830: I/DEBUG(1918): bed3f248 00000000 570c9cb8 40d81068 40d81068 .......Wh..@h..@
11-05 18:32:15.830: I/DEBUG(1918): code around pc:
11-05 18:32:15.830: I/DEBUG(1918): 40886874 0005213e 460db57f 21014604 46162000 >!.....F.F.!. .F
11-05 18:32:15.830: I/DEBUG(1918): 40886884 faaef019 46296823 f01068d8 6831fafd ....#h)F.h....1h
11-05 18:32:15.830: I/DEBUG(1918): 40886894 68004605 d0154288 fce6f031 6930b990 .F.h.B..1.....0i
11-05 18:32:15.830: I/DEBUG(1918): 408868a4 490a6833 68289000 4a094479 447a6980 3h.I..(hyD.J.izD
11-05 18:32:15.830: I/DEBUG(1918): 408868b4 20059001 f7e3699b 4620ee24 fb88f7ff ... .i..$. F....
11-05 18:32:15.830: I/DEBUG(1918): code around lr:
11-05 18:32:15.830: I/DEBUG(1918): 40886870 0005179c 0005213e 460db57f 21014604 ....>!.....F.F.!
11-05 18:32:15.830: I/DEBUG(1918): 40886880 46162000 faaef019 46296823 f01068d8 . .F....#h)F.h..
11-05 18:32:15.830: I/DEBUG(1918): 40886890 6831fafd 68004605 d0154288 fce6f031 ..1h.F.h.B..1...
11-05 18:32:15.830: I/DEBUG(1918): 408868a0 6930b990 490a6833 68289000 4a094479 ..0i3h.I..(hyD.J
11-05 18:32:15.830: I/DEBUG(1918): 408868b0 447a6980 20059001 f7e3699b 4620ee24 .izD... .i..$. F
11-05 18:32:15.910: I/DEBUG(1918): !@dumpstate -k -t -z -d -o /data/log/dumpstate_app_native -m 7822
11-05 18:32:15.910: I/BootReceiver(2300): Copying /data/tombstones/tombstone_03 to DropBox (SYSTEM_TOMBSTONE)
11-05 18:32:15.920: I/dumpstate(8149): begin
Whan I called setUsingNativeTitleBar() I just wanted to hide the caption of my window to let the application use more screen space. Is there any other way to do this?