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moved info on diagnosing crashes to debugging page
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==Debugging Tip==
−When faced with a crash in your Homebrew, often you'll see a code dump with an address and some machine code. Here's my trick to track that back to a line of C++ code.
−For example if your homebrew game crashes it might show something like this:
− CODE DUMP:
−
− 800084ac: 809F0020 2F840000 ...
− 800084bc: ...
− 800084cc: ...
−The 800084ac is the memory address in hex of where the crash occurred. 809F0020 is the machine code for the offending instruction.
−*Step 1:
−In your makefile change the CXXFLAGS line to the following:
− CXXFLAGS = -save-temps -Xassembler -aln=$@.lst $(CFLAGS)
−The "-save-temps" will save the assembly language file, which can be interesting.
−The "-Xassembler -aln=$@.lst" creates a list file which contains the assembly and the machine code.
−Now recompile your entire project.
−Note, this just affects C++ code.
−*Step 2:
−Look at the map file that was built. The mapfile is on by default in the Wii template makefile. Typically it's in the build subdirectory and called something.map. Look in that mapfile for the nearest memory address that doesn't go over the one found in the CODE DUMP. Here is an example:
− 0x80008464 ShooterView::Render(BibGraphicsDevice&)
−This tells me that the crash was 72 bytes into the ShooterView::Render() function. Now to find the line number in Render()
−*Step 3:
−Look at the list file for the relevant function. Here's an example:
− 473 .globl _ZN11ShooterView6RenderER17BibGraphicsDevice
− 474 .type _ZN11ShooterView6RenderER17BibGraphicsDevice, @function
− 475 _ZN11ShooterView6RenderER17BibGraphicsDevice:
− 476 .LFB1465:
− 477 .loc 1 158 0
− 478 .LVL20:
− 479 02d0 9421FF00 stwu 1,-256(1)
−The function names are mangled because this is C++ code. See http://en.wikipedia.org/wiki/Name_mangling#Name_mangling_in_C.2B.2B
−The address of the first instruction of Render() is at 02d0. This is also line 158 in the file (".loc 1 158 0"). To find the error location, just look at 0x2d0 + 72 = 0x318. See below:
− .loc 1 168 0
− 528 0314 809F0020 lwz 4,32(31)
− 529 0318 2F840000 cmpwi 7,4,0
−This shows machine address 0x318 has the proper machine code and the nearest .loc statement says the problem is at line 168 of the ShooterView.cpp.
−For more info on the assembler output see the manual here: http://sourceware.org/binutils/docs-2.18/as/index.html
Or use SYS_RETURNTOMENU for a "soft" return to the system menu, SYS_POWEROFF to shut down the wii (automatically to the appropriate Idle or Standby mode, depending on the WC24 setting), or SYS_POWEROFF_STANDBY or _IDLE to specify the mode and override the system setting.
Or use SYS_RETURNTOMENU for a "soft" return to the system menu, SYS_POWEROFF to shut down the wii (automatically to the appropriate Idle or Standby mode, depending on the WC24 setting), or SYS_POWEROFF_STANDBY or _IDLE to specify the mode and override the system setting.
−==General Programming Tips==
==General Programming Tips==