This is the mail archive of the cygwin mailing list for the Cygwin project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Differences between C++ 'new' operator and 'malloc()' (NOT a C/C++ question)

On 04/07/2012 5:45 AM, Claude SIMON wrote:
When I compile the component with Visual C++, it works. When I compile the
component with g++... it crashes.

With 'gdb', I found that the problem happens when calling the 'malloc'
function (as soon as the function is called, NOT when the returned
allocated memory is used). When I replace the 'malloc' by a the C++ 'new'
operator, the component compiled with Cygwin g++ doesn't crash anymore.

I thought that the C++ 'new' operator calls the 'malloc' function, but
this seems not to be the case. As I want to use 'malloc'-like functions
rather than the C++ 'new' operator, I wonder which functions are used in
the C++ 'new' operator to allocate memory (and naturally which functions
are used in the C++ 'delete' operator to free the memory).
Operator new() and malloc() are explicitly *not* interchangeable (for many reasons, not least of which that the Standard says so). If you were to free new'ed memory, or delete malloc'ed memory, the resulting heap corruption could easily manifest as a crash the next time you tried to allocate something... or it might just silently clobber data and lead to "spooky action at a distance."


-- Problem reports: FAQ: Documentation: Unsubscribe info:

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]