Uninitialized value was created by a heap allocation
In the updated code you use an uninitialized pointer: As people had wrote already, this will only work if you had pre-set all the pointers to be NULL before entering this loop:
valgrind
Valgrind permission denied on file
I am running Ubuntu 12.04 and installed Valgrind configure and installed it. Everytime i run valgrind ./ file I always get permission denied even under root.
Interpreting valgrind error Invalid write of size 4
points_read is most likely out of bounds, you’re writing past (or before) the memory you allocated for amplitudes.
valgrind – Address —- is 0 bytes after a block of size 8 alloc’d
strcpy adds a null terminator character ‘\0’. You forgot to allocate space for it: You need to add space for 5 characters: 4 for “.tde” suffix, and one more for the ‘\0’ terminator. Your current code allocates only 4, so the last write is done into the space immediately after the block that you have … Read more
How to run valgrind with basic c example?
It looks good. You only need to add a ./ before your executable. Without it, valgrind fails to find it and reports ‘command not found’.
Valgrind: Invalid read of size 1
How to read this: Invalid read of size 1 Your program is trying to read one byte from somewhere that Valgrind doesn’t like. at 0x401569: main (:395) Where in the code this happens (clearly strcmp has been inlined) Address 0x0 is not stack’d malloc’d or (recently) free’d What the address it was reading – 0x0 … Read more
C free(): invalid pointer
You’re attempting to free something that isn’t a pointer to a “freeable” memory address. Just because something is an address doesn’t mean that you need to or should free it. There are two main types of memory you seem to be confusing – stack memory and heap memory. Stack memory lives in the live span of the function. … Read more
Uninitialised value was created by a stack allocation
The meaning of the error is essentially that you’re using a variable before you assign to it. The only variables this can possibly apply to are dd, mm, yy. This means that your sscanf call is not writing to all three of them. This will occur if you pass in a date that isn’t completely specified. Note that sscanf returns a value … Read more
Invalid read of size 8 – Valgrind + C
The problem is that you’re freeing the sym, then trying to access a value from the (now-freed) data: sym->next. You probably want something like this for the inner loop:
How do I use valgrind to find memory leaks?
Try this: valgrind –leak-check=full -v ./your_program As long as valgrind is installed it will go through your program and tell you what’s wrong. It can give you pointers and approximate places where your leaks may be found. If you’re segfault’ing, try running it through gdb.