Is constructing an object in an argument list and passing a pointer to internal data of the object to the function safe?

Question

Is the C++ code below well-formed? Will the std::string get destroyed before or after the function finishes executing?

void my_function(const char*);

...

my_function(std::string("Something").c_str());

But seriously, the temporary string will die at the end of the expression. That'll be after the function call. So long as my_function doesn't store that pointer somewhere with a longer life you're good. — 11 hours ago
I'm surprised I can't find a good duplicate of this. Closest I got is this. — 11 hours ago
Here's the canonical documentation and some supporting information on when the expression ends. Took longer to find than I thought it would. But go with the stuff at CPP reference. I reads like it was translated from Martian, but in a way that's because it was. — 11 hours ago

user17732522user17732522 50k2 gold badges53 silver badges100 bronze badges · Accepted Answer · 2023-07-28 00:26:14Z

Will the std::string get destroyed before or after the function finishes executing?

Temporary objects are destroyed (with some exceptions, none relevant here) at the end of the full-expression in which they were materialized (e.g. typically the end of an expression statement).

The std::string object here is such a temporary materialized in the full-expression that spans the whole my_function(std::string("Something").c_str()); expression statement. So it is destroyed after my_function returns in your example.

Is constructing an object in an argument list and passing a pointer to internal data of the object to the function safe?