Question

In C for example, there is no malloc() without a runtime library (libc). And I think for example, on Windows malloc just calls HeapAlloc(). But in C++, the way to allocate dynamic memory is actually a keyword of the language; same for “delete”. So therefore, how would “new” work if you compiled your code without a runtime library?

Thanks

Answer 1

If new operator is not overloaded, it is generally the same as malloc function. It is platform dependent. The only difference, is that it automatically manage the initialization of the data.

EDIT:

On linux you can not compile without standard library. You got the following message:

phong@colinux ~ $ g++ -nostdlib test.cpp
/usr/bin/ld: warning: cannot find entry symbol _start; defaulting to 00000000080480d8
/tmp/ccOV36hW.o: In function `main':
test.cpp:(.text+0x11): undefined reference to `operator new(unsigned int)'
test.cpp:(.text+0x21): undefined reference to `operator delete(void*)'
/tmp/ccOV36hW.o:(.eh_frame+0x12): undefined reference to `__gxx_personality_v0'
collect2: ld returned 1 exit status