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#include <stdio.h> void bar(int n, const char *p[]) { for (int i = 0; i < n; i++) { printf("%s\t", p[i]); } putchar('\n'); } #define bar(...) (bar( \ sizeof((const char*[]) { NULL, __VA_ARGS__ }) / sizeof(const char*) - 1, \ (const char*[]) { NULL, __VA_ARGS__ } + 1)) int main(/* int argc, char **argv */) { bar(); bar("a"); bar("a", "b"); bar("a", "b", "c"); return 0; }

Compiled with /EHsc /nologo /W4 /c main.cpp main.cpp(20): error C4576: a parenthesized type followed by an initializer list is a non-standard explicit type conversion syntax main.cpp(21): error C4576: a parenthesized type followed by an initializer list is a non-standard explicit type conversion syntax main.cpp(22): error C4576: a parenthesized type followed by an initializer list is a non-standard explicit type conversion syntax main.cpp(23): error C4576: a parenthesized type followed by an initializer list is a non-standard explicit type conversion syntax

If you don't need the return value, the do-while approach works as you suggested:

  #define bar(...) do {		                   	 \
	const char *_args[] = {NULL, __VA_ARGS__};       \
	bar(sizeof(_args)/sizeof(*_args) - 1, _args + 1);\
  } while (0)

If for some absurd reason you really do need to emulate a "compound statement expression" in MSVC (because you need to declare some temp variables in a macro that can be used for assignment), it turns out that it can be done with a "lambda expression":

  #include <stdio.h>

  int bar(int n, const char *p[])
  {
    int total = 0; 
    for (int i = 0; i < n; i++) {
      total += printf("%s\t", p[i]);
    }
    putchar('\n');
    return total;
  }

  #define bar(...) [](){                                       \
    const char *_args[] = {NULL, __VA_ARGS__};                 \
    return bar(sizeof(_args)/sizeof(*_args) - 1, _args + 1);   \
  }()

  int main(/* int argc, char **argv */) {
    int total = 0;
    total += bar();
    total += bar("a");
    total += bar("a", "b");
    total += bar("a", "b", "c");
    printf("total: %d\n", total);
    return 0;
  }