https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81129

            Bug ID: 81129
           Summary: GCC successfully compiles expression into nothing
           Product: gcc
           Version: 7.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: antoshkka at gmail dot com
  Target Milestone: ---

The following code successfully compiles by GCC with -std=c++11 and -std=c++03:


void print(bool) { throw 1; }

int main() {    
    void(*)(bool){&print}(false);  
}


The bad thing is that people expect the code to be a construction of a function
pointer, initialization of it to the address of `print` function and call of
that function. That's not what happens. The whole expression is removed from
the resulting assembly.


Clang fails to compile the code:

main.cpp:4:11: error: expected expression
    void(*)(bool){&print}(false);  
          ^

main.cpp:4:17: error: expected '(' for function-style cast or type construction
    void(*)(bool){&print}(false);  
            ~~~~^

Please, either make the expression work as expected, or issue a warning, or
fail to compile.

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