Can we inspect an object file for presence of temporaries introduced by C++ compiler?

Question

Is there a way to inspect object file generated from code below ( file1.o ) for presence of compiler introduced temporary? What tools can we use to obtain such info from object files?

//file1.cpp
void func(const int& num){}
int main(){   func(2);  }

Answer 1

The easiest way I can think of to do this is to load up a program that uses the object file and disassemble the function in the debugger. The program code you posted would work fine for this. Just break on the call to func and then display the assembler when you single-step into the function.

In a more complex program you can usually display the assembler code for a given function by name. Check your debugger documentation for how to do this. On Windows (Visual Studio) you can open the Disassembly window and enter the name of the function to display the assembler code.

If you have the source, most compilers allow you to output assembler, sometimes mixed with the source code. For Visual C++ this is /Fa.

Answer 2

If you're on an ELF system and have GNU binutils you can call readelf, probably with the -s switch.

Answer 3

If you have the source available, it is probably easier to look at the assembler file generated by the compiler (-save-temps for gcc). Otherwise, objdump is your friend.

Answer 4

You can use clang -cc1 --ast-print-xml to get a XML representation of a translation unit. The presence of temporaries can be easily detected from the AST.