Compiler support of GNU Statement Expression

问题

Which modern compilers support the Gnu Statement expression (C and C++ languages). What versions should I have to use a statement expressions?

Statement expression is smth like ({ code; code; retval }):

int b=56;
int c= ({int a; a=sin(b); a})

I already know some such compilers:

GCC >=3
Clang/LLVM >= ?
Intel C++ Compiler >= 6.0 (Linux version, check page 4; bit limited)
Sun Studio >= 12 (New Language Extensions)
IBM XL for z/OS (marked as IBM extension)
Open64 (as it uses osprey-gcc frontend)

This compiler seems not to support this (i'm unsure):

MS Visual C++

PS. some C/C++ compilers are listed here but I interested only in mature compilers, that are used widely (e.g not a tcc or turbo c)

回答1:

The PathScale® EKOPath Compiler Suite

It support gnu99 with "−std=gnu99"

回答2:

The Intel C++ Compiler does not support statement expressions, even the last version that I know, version 13.0.

回答3:

As said in the comment of my previous answer, the Intel Compiler does support the statement expressions. But the emulation by Intel of that GNU extension is not complete, in C++. The following code is taken from CGAL-4.0 (http://www.cgal.org/):

#include <cassert>

struct A {
  int* p;

  A(int i) : p(new int(i)) {}
  ~A() { delete p; }
  int value() const { return *p;}
};

int main()
{
  int i = __extension__ ({ int j = 2; j+j; });
  assert(i == 4);

  // The Intel Compiler complains with the following error:
  // "error: destructible entities are not allowed inside of a statement
  // expression"
  // See http://software.intel.com/en-us/articles/cdiag1487/
  i = __extension__ ({ A a(2); A b(3); a.value() + b.value(); });

  assert(i == 5);
  return 0;
}

A comment in the code even give the error returned by the Intel Compiler, tested with version 11, 12, or 13.

http://software.intel.com/en-us/articles/cdiag1487/

来源：https://stackoverflow.com/questions/6440021/compiler-support-of-gnu-statement-expression

标签

visual-c++

compiler-construction

c99