Bug 4710 – writeln crashes when called from C code.

Given the following content: // x.d import std.stdio; extern (C) void foo() { writeln("1"); } // y.c void foo(void); int main () { foo(); return 0; } And compile and run with gcc -c -m32 y.c -o y.o dmd x.d y.o -ofx ./x Result in a Bus Error on Mac OS X. (I am using dmd r620, druntime r370 and Phobos r1900.)

When calling from C you have to explicitly initialize D's runtime first. Your program calls Phobos function on uninitialized druntime and will obviously crash. For more information read this: http://stackoverflow.com/questions/7480046/implementing-a-c-api-in-d/7486417#7486417