2011/6/12 Georg-Johann Lay <a...@gjlay.de>: > Marcin S schrieb: >> >> 2011/6/11 Georg-Johann Lay <a...@gjlay.de>: >>> >>> Marcin S schrieb: >>>> >>>> 2011/6/9 Georg-Johann Lay <a...@gjlay.de>: >>>>> >>>>> Marcin S schrieb: >>>>> >>>>>> Hello there, >>>>>> >>>>>> from time to time i have a strange problems when initializing >>>>>> class objects in file range by their respective >>>>>> constructors, i noted that problem occurs only when that >>>>>> constructors takes pointers to other global objects, tables >>>>>> or something else. >>>>>> >>>>>> Whats the problem? in best scenario object pointer are >>>>>> wrongly set and pointing to some random locations, at worst >>>>>> my program does not start at all (event with my main() func >>>>>> empty) it just hangs >>>>>> >>>>>> here is link to my code >>>>>> http://dl.dropbox.com/u/6883398/Lays.tar.bz2 its and eclipse project, >>>>>> simple "make" in project directory should work too. >>>>>> Note that archive contains already compiled program in >>>>>> "Release" directory, this compilation does not work at all! >>>>>> (worst case scenario described above). >>>>>> >>>>>> As I wrote this program incrementaly it stopped working after >>>>>> i added 2 objects inits in layouts.cpp >>>>>> >>>>>> CLayPGMString minTag(minTagData,strMin,true,CLayPGMString::XSMALL); >>>>>> CLayPGMString maxTag(maxTagData,strMax,true,CLayPGMString::XSMALL); >>>>>> >>>>>> strMin and strMax params are pointers to strings in PROGMEM, >>>>>> if i replace it with zeros like >>>>>> >>>>>> CLayPGMString >>>>>> minTag(minTagData,0,true,CLayPGMString::XSMALL); CLayPGMString >>>>>> maxTag(maxTagData,0,true,CLayPGMString::XSMALL); >>>>>> >>>>>> program starts again. >>>>>> >>>>>> Other important thing noted is, when I initialise those >>>>>> objects in file range with their default, empty constructors >>>>>> and then set needed pointers at run time (for example right >>>>>> after main() function) everything works too. I ran out of >>>>>> ideas what could be wrong, maybe wrong code, I'm open to any >>>>>> suggestions. >>>>>> >>>>>> I'm using avr-gcc-4.5.2 on gentoo linux, also checked on >>>>>> stable 4.4 and it behaves exactly the same way. >>>>>> >>>>>> Marcin >>>>> >>>>> Do you see r20 used in one of the functions? Reminds me of >>>>> http://gcc.gnu.org/PR45263 which is not yet backported to >>>>> avr-gcc < 4.6 >>>>> >>>>> Johann >>>> >>>> Hej Johann, >>>> >>>> I'm not sure if i checked it correctly, I've opened .lss file >>>> corresponding to my program and yes, there are some r20 >>>> operations in this function. >>>> >>>> Excuse me my lack of knowledge of low lvl stuff, but You think >>>> this might cause the problem? >>> >>> That depends on the hardware you use. The problem will not occur on >>> devices <= 64 kib flash. Look at the code again. In the startup >>> code that runs before main you might see use of r20 around calls to >>> you function. Note that these calls will be indirect, so searching >>> for symbol will not help. Using r20 that way in startup can cause >>> problems because is is callee-used register and the callee can >>> clobber it, leaving its content in a mess in startup code. >>> >>>> Marcin >>> >>> Johann >> >> Hi, It's atmega128, so r20 still is a main suspect. >> >>> Note that these calls will be indirect, so searching for symbol >>> will not help. >> >> Umm, then I'm afraid I dont know how to check it. >> >> Btw. I tried to confirm this thinking by building 4.6.1 avr-gcc but i >> think its buggy atm (dwarf2 bug) and i am unable to build any > > Yes, that's PR48459: DWARF is unusable in current 4.6 and 4.7, so using > DWARF or configuring with --with-dwarf2 will abort. > > If you build the compiler on your own, you can simply copy > ./gcc/config/avr/libgcc.S > from 4.6 or 4.7 into your 4.5 sources. Or you can build 4.6 without dwarf > and copy the generated libgcc.a's in respective places in your installed > compiler (no matter if win32 or linux). > >> project with it. I'll wait till it will be usable and let You know. >> >> Marcin. > >
I've picked this way > Or you can build 4.6 without dwarf > and copy the generated libgcc.a's in respective places in your installed > compiler did that with my current 4.4 ... and its working! :-D at least on early testing (but couldnt hold myself with sharing it now :P) I also checked another project, bigger, with simmilar issues in wchich i had to reinitialize almost all pointers at run-time to get it working - now its okay witout it. Thanks You very much for assistance. Marcin. _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org https://lists.nongnu.org/mailman/listinfo/avr-gcc-list
