Home > Invalid Pointer > Invalid Pointer In C

Invalid Pointer In C

Contents

Or point to an random location in the address space of the process. Of course, those are not pointers allocated by malloc() (or similar), so free()ing them is undefined behavior. An example:int *f() { int n = 5; return &n; }; The function returns an invalid pointer because the variable n is freed when the function exits.350 Views · View UpvotesRelated Custom exception for string that is too long Why do we use the electron volt? Check This Out

thanks a lot. "free(): invalid pointer" probably means that the function 'free' was given a pointer which did not point to an allocated memory area. Soldier mentioned in War Dogs What makes a language "optimized" for a specific task? I'm running it on a cluster, if that makes any difference. Ubuntu Logo, Ubuntu and Canonical Canonical Ltd.

Free() Invalid Pointer C++

Not the answer you're looking for? Custom exception for string that is too long Wind mills in empty fields. Those pointers are stored in the heap, so we might be seeing pointer corruption from some out of bounds access to your arrays. With my misunderstanding of pointers though, I thought I needed to point to z's address to p2 to accomplish this.

Memory is usually byte aligned depending on OS and system, and you are working with 8 byte values (64 bit double precision floats). I changed the statement p2 = &z; to *p2 = z; as laserlight suggested in order to maintain the memory address malloc provided and it works now. All rights reserved. Free Invalid Pointer Glibc Detected z has a different memory address from p2.

Programs allocate blocks from the heap by calling the malloc function." ~Computer Systems : A Programmer's Perspective, 2nd Edition, Bryant & O'Hallaron, 2011 EDIT 2: * The C standard does not, User contributions on this site are licensed under the Creative Commons Attribution Share Alike 4.0 International License. Meaning of "Sue me" Starting off with shimano gears more hot questions question feed lang-c about us tour help blog chat data legal privacy policy work here advertising info mobile contact Also, I've looked up malloc and it seems that it does, in fact, allocate heap memory. –GraphicsMuncher Nov 30 '13 at 7:48 1 The unnecessary copy is, well, unnecessary and

I find that 90% of the time it directs me straight to the bug. -- Richard -- "Consideration shall be given to the need for as many as 32 characters in Invalid Pointer Error In C I recommend using the program 'valgrind' to find the error. All rights reserved. You can avoid strdup() and free() altogether by simply writing char *s = p;.

Free() Invalid Pointer Aborted (core Dumped)

Browse other questions tagged c pointers free valgrind or ask your own question. Outside of your DOS world, your header file is meaningless. Free() Invalid Pointer C++ When i put those back in. Error In Free() Invalid Pointer C++ However, for anyone learning on a relevant desktop/laptop machine, the distinction is probably unnecessary and confusing if anything, especially if you're learning about how your program is stored and executed.

Heap memory lives from when you malloc it to when you free it. his comment is here Not that I know of. temp = malloc(sizeof(char)*strlen(a)+1); char *original_temp = temp; while(*temp){ // processing temp++; } free(original_temp); share|improve this answer answered Feb 2 '15 at 2:10 Yu Hao 84.9k20121180 add a comment| up vote 1 Either you have done 'delete' on something which was not an object, or something else has happened that has corrupted the memory structure, like writing outside an array. What Is Invalid Pointer

Please don't PM me for help - and no, I don't do help over instant messengers. 09-05-2008 #3 dwks View Profile View Forum Posts Visit Homepage Frequently Quite Prolix Join Date If not, you have the perfect piece of code to bring here and ask for help. –sbi Jan 28 '12 at 7:36 add a comment| 2 Answers 2 active oldest votes How to avoid const cast for map access? http://magsuite.com/invalid-pointer/invalid-pointer.html If you can get the program down to a reasonably small chunk of code that shows the problem we can take a look at it. -- Flash Gordon Sep 30 '07

Thank you. ============================== *** glibc detected *** ./server: free(): invalid pointer: 0x08641a38 *** ======= Backtrace: ========= /lib/i386-linux-gnu/libc.so.6(+0x6b961)[0xefe961] /lib/i386-linux-gnu/libc.so.6(+0x6d28b)[0xf0028b] /lib/i386-linux-gnu/libc.so.6(cfree+0x6d)[0xf0341d] /usr/lib/i386-linux-gnu/libstdc++.so.6(_ZdlPv+0x21)[0x4c74d1] ./server[0x804b499] ./server[0x804b2ad] ./server[0x804aecd] ./server[0x804ad36] ./server[0x804a3a3] /lib/i386-linux-gnu/libc.so.6(+0x2fa6f)[0xec2a6f] /lib/i386-linux-gnu/libc.so.6(+0x2facf)[0xec2acf] ./server[0x804966b] /lib/i386-linux-gnu/libc.so.6(__libc_start_main+0xe7)[0xea9e37] ./server[0x8049331] ======= Attempt To Free Invalid Pointer Most have more sense than to send me hundreds of lines of code. For example: Up Next Now Calculating … The Famous Algorithms Quiz How does JavaScript work and how can I build simple calculators with it?

Just because something is an address doesn't mean that you need to or should free it.

Mainly, I was hoping someone has some insight as to why this error is occurring even after all free()s have been removed from my code. Join them; it only takes a minute: Sign up C free(): invalid pointer up vote 2 down vote favorite 1 I am teaching myself C. share|improve this answer edited Nov 30 '13 at 7:06 answered Nov 30 '13 at 7:01 user529758 That worked. Invalid Pointer Windows 7 Login Why is pattern "command || true" useful?

This can make this error very hard to track down. Modifying f[7] can corrupt someone else's memory. 2) If you save a pointer to an object allocated on the stack, that object goes out of scope, and then you modify something share|improve this answer answered Nov 30 '13 at 7:04 Tim Pierce 3,819926 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google navigate here Get Started with C or C++ C Tutorial C++ Tutorial Get the C++ Book All Tutorials Advanced Search Forum General Programming Boards C Programming Program crashing on free() with an invalid

Make companies apply to you with in-depth job info up front.Sign Up at Hired.com/signupAnswer Wiki2 Answers James McInnes, well-rounded individiualWritten 71w agoThe term generally refers to a pointer that doesn't point Bug #3 - Zero Pointer Reference A zero pointer reference occurs whenever a pointer pointing to zero is used in a statement that attempts to reference a block. Is there an optional or house rule for effectiveness of specific weapons versus specific armor types? Thank you c malloc free glibc share|improve this question asked Feb 2 '15 at 2:07 user3314878 144 add a comment| 2 Answers 2 active oldest votes up vote 1 down vote

Register Remember Me? Why would a crash landed generation fall back to the stone age? Adv Reply Quick Navigation Programming Talk Top Site Areas Settings Private Messages Subscriptions Who's Online Search Forums Forums Home Forums The Ubuntu Forum Community Ubuntu Official Flavours Support New to Many people have trouble with pointers.

vBulletin 2000 - 2016, Jelsoft Enterprises Ltd. You almost certainly have some kind of out-of-bounds pointer error. What does an exclamation mark mean in diff output? My OS Is Open Source - An Ubuntu and Linux Quiz Why are there so many different image formats on the Web?

Sorry! –MitchellSalad Jan 28 '12 at 7:33 1 @MitchellSalad: In the course of reducing your code to a repro case (<50LoC, self-contained, reproducing the problem) you are very likely to c pointers memory-management free share|improve this question edited Jun 4 '12 at 16:15 asked Jun 1 '12 at 14:54 Alex 84211431 In your if statement, you only need to Using Threads to create GameObjects more hot questions question feed lang-c about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life Similar topics Help : glibc detected *** ./a.out: free(): invalid next size (normal): 0x099da890 Better free(invalid pointer) behavior?

By Syneris in forum C++ Programming Replies: 6 Last Post: 12-29-2005, 09:40 PM Question About Pointer To Pointer By BlitzPackage in forum C++ Programming Replies: 2 Last Post: 09-19-2005, 11:19 PM When you call the function main, it sets aside some memory for your variables you've declared (p,token, and so on). The important point is that it was not allocated by the standard allocator functions. –user529758 Nov 30 '13 at 7:14 Also, suggesting an unnecessary copy is kind of pointless.