Geek asks and answers

Why can't -O0 fail to disable gcc compilation?

string str="fujian";

Some books say that the code calls the copy constructor, but g ++ optimizes it so that the copy constructor is not called.

However, I used the g ++ -O0 command to disable optimization, but it still cannot call the copy constructor.

How to understand this?

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2 answers

With GCC and Clang, you can use the compilation flag -fno-elide-constructorsto disable copy / move optimization optimizations.

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