Gcc Bus Error 10
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Bus Error: 10 Node
vote favorite 3 I am trying reverse a string. This is the code I tried: #include
challenged and removed. (July 2015) (Learn how and when to remove this template message) In computing, a bus error is a fault raised by hardware, notifying an operating system (OS) that a process is trying to access memory bus error (core dumped) linux that the CPU cannot physically address: an invalid address for the address bus, hence
How To Debug Bus Error
the name. In modern use on most architectures these are much rarer than segmentation faults, which occur primarily due to memory
How To Solve Bus Error In Linux
access violations: problems in the logical address or permissions. On POSIX-compliant platforms, bus errors usually result in the SIGBUS signal being sent to the process that caused the error. SIGBUS can also be caused http://stackoverflow.com/questions/7458854/bus-error-troubleshooting by any general device fault that the computer detects, though a bus error rarely means that the computer hardware is physically broken—it is normally caused by a bug in a program's source code.[citation needed] Bus errors may also be raised for certain other paging errors; see below. Contents 1 Causes 1.1 Non-existent address 1.2 Unaligned access 1.3 Paging errors 2 Example 3 References Causes[edit] There are at least three main https://en.wikipedia.org/wiki/Bus_error causes of bus errors: Non-existent address[edit] Software instructs the CPU to read or write a specific physical memory address. Accordingly, the CPU sets this physical address on its address bus and requests all other hardware connected to the CPU to respond with the results, if they answer for this specific address. If no other hardware responds, the CPU raises an exception, stating that the requested physical address is unrecognized by the whole computer system. Note that this only covers physical memory addresses. Trying to access an undefined virtual memory address is generally considered to be a segmentation fault rather than a bus error, though if the MMU is separate, the processor can't tell the difference. Unaligned access[edit] Most CPUs are byte-addressable, where each unique memory address refers to an 8-bit byte. Most CPUs can access individual bytes from each memory address, but they generally cannot access larger units (16 bits, 32 bits, 64 bits and so on) without these units being "aligned" to a specific boundary (the x86 platform being a notable exception). For example, if multi-byte accesses must be 16 bit-aligned, addresses (given in bytes) at 0, 2, 4, 6, and so on would be considered aligned and therefore accessible, while addresses 1, 3, 5, and
I'm not pointing my finger at gcc here, this is a Sun gotcha).Here's an example program (simplified for something much more complex that I was debugging), that illustrates how memory alignment on SPARC systems can bite you if you are doing low-level things in C. In the example the program allocates space for a thing structure which will be prepended with a header. The header structure has a dummy byte array called data which will be used to reference the start of the thing.struct thing { int an_int;};struct header { short id; char data[0];};struct header * maker( int size ) { return (struct header *)malloc( sizeof( struct header ) + size );}int main( void ) { struct header * a_headered_thing = maker( sizeof( struct thing ) ); struct thing * a_thing = (struct thing *)&(a_headered_thing->data[0]); a_thing->an_int = 42;}If you build this on a SPARC machine you'll get the following error when you run it:Bus Error (core dumped)Annoyingly, if you build a debugging version of this program the problem magically goes away and doesn't dump core in the debugger. So you either resort to printf-style debugging or going into gdb and looking at the assembly output.Here's what happens when you run this in gdb (non-debug code):(gdb) runProgram received signal SIGSEGV, Segmentation fault.0x000106d8 in main ()Since you can't get back to the source we're forced to do a little disassembly:(gdb) disassembleDump of assembler code for function main:0x000106b0