I received a question from Dicebot in at the end of my presentation. He asked about the --gc-sections linker flag breaking code from GDC.

I recently discovered how one can see why this is occurring, and I hope this will help identify the problem and lead to a solution.

Compile any simple hello world program with the following gcc command:
gcc --verbose -Wl,--verbose test.c.

Part of the output is GCC's internal linker script as shown below. I believe this is the source of the problem. Here's my theory.

D is not C, and is likely generating code that the GCC internal linker script doesn't know about. This code may be incorrectly identified as dead code because there is no 'link' to it and, therefore, appears unused. If D or GDC is generating any code like this, it needs to be marked as KEEP in the linker script. You can see examples of this in GCC's internal linker script below.

If my theory is correct, GDC may have to make an internal linker script specifically for D's code generation that marks such code as KEEP.

I hope I'm not just blowing smoke.

Mike

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