这个调试断言失败是什么意思？

Question

Expression: header->_block_use == block_use || header->_block_use == _CRT_BLOCK && block_use == _NORMAL_BLOCK

What does this mean? It has something to do with a header?

I found in my code where after I step over it returns the debug assertion failure, just this one line of code works in other projects.

Is there a linker setting or c/c++ setting that I have to remove?

Answer 1

The assertion that you are hitting is part of the Microsoft Visual C/C++ runtime libraries, specifically related to the debug heap . Calling malloc / free and using the new / delete operators leads to calls to the CRT heap functions, which perform internal consistency checks using these assertions.

It's very likely that the assertion is hit as a result of a memory safety bug, for example trying to delete a garbage pointer, double-free, etc. If you are unable to find it, the ASAN tool can help by keeping closer track of memory operations and raising errors when your code does invalid things. Without these close checks, mistakes in your code can corrupt a data structure, and the crash could occur much, much later in unrelated code.

For Visual Studio, it involves a few steps : the "C++ AddressSanitizer" feature must be installed using the Visual Studio installer, and the address sanitizer must be enabled in the project properties under C/C++ -> General.

Answer 2

Languages such as C and C++ offer an assert(...expression...) facility that is typically used during debugging... and omitted from the final delivered product. The ..expression... being "something that should always be False."

If the expression turns out not to be False, then it throws a runtime exception containing the exact text of expression . Which is exactly what a developer would like to see, because: "the whole idea is that this should never, ever, ever happen!"

Ordinarily, published versions of applications are compiled in such a way that all of the assert() statements are ignored: they are "no-ops."