ks1322 ks1322 - 1 month ago 12
C++ Question

Is there Valgrind Memcheck like tool for windows to debug use after free errors?

Durring my work I regulary face rather common programming error - using some object which has already been freed. This invokes UB in C++. On linux, this kind of problems are usually resolved by using Valgrind tool Memcheck. From Memcheck manual:


Memcheck tries to establish what the illegal address might relate to,
since that's often useful. So, if it points into a block of memory
which has already been freed, you'll be informed of this, and also
where the block was freed.


Memcheck provides me call stack, where the object was deallocated and I can go on and debug the problem. Is there similar tool for windows with the same functionality, preferably free?

Answer Source

According to Dr. Memory documentation, there is -delay_frees_stack option with exactly the same Valgrind functionality. From Option Reference:

-delay_frees_stack 
default: false 
Record callstacks on free to use when reporting use-after-free or other errors that overlap with freed objects. There is a slight performance hit incurred by this feature for malloc-intensive applications.

Also here is an example of error reported by Dr. Memory:

Here is another example, using the -delay_frees_stack option to obtain the callstack of the freed memory:

Error #8: UNADDRESSABLE ACCESS: reading 0x001338a8-0x001338ac 4 byte(s)
# 0 unaddr_test1                    [e:\derek\drmemory\git\src\tests\suppress.c:110]
# 1 test                            [e:\derek\drmemory\git\src\tests\suppress.c:269]
# 2 main                            [e:\derek\drmemory\git\src\tests\suppress.c:297]
Note: @0:00:02.141 in thread 3024
Note: next higher malloc: 0x001338e8-0x00133938
Note: prev lower malloc:  0x001337e8-0x00133820
Note: 0x001338a8-0x001338ac overlaps memory 0x001338a8-0x001338c4 that was freed here:
Note: # 0 test                            [e:\derek\drmemory\git\src\tests\suppress.c:269]
Note: # 1 main                            [e:\derek\drmemory\git\src\tests\suppress.c:297]
Note: instruction: mov    (%eax) -> %eax