Veikka Tuominen

`.truncate = false` should be fixed to not truncate the file.

I don't have too strong of an opinion about it, I guess there could be value to asserting a file exists before appending to it?

Cannot reproduce on `0.14.0-dev.302+d404d8a36`: ``` a.zig:19:15: error: expected type 'fn (c_uint) ?*cimport.struct_passwd', found 'fn (c_uint) callconv(.C) [*c]cimport.struct_passwd' callback(c.getpwuid); ~^~~~~~~~~ a.zig:19:15: note: calling convention 'C' cannot cast into calling convention 'Unspecified'...

``` thread 15270 panic: reached unreachable code Analyzing a.zig %61 = ret_type() node_offset:18:1 to :18:7 %62 = dbg_stmt(2, 5) %63 = decl_val("callback") token_offset:19:5 to :19:13 %64 = dbg_stmt(2, 13) >...

Incorrect error message fixed in #19620 but it could still be better ``` a.zig:18:23: error: no field named '0' in struct 'a.Range' var r: Range = foo(10, 20); ~~~^~~~~~~~ a.zig:22:15:...

> One thing that’s notable is that this only happens when the format is supposed to be inferred by the file extension (by adding .zig at the end). So this...

This doesn't seem to work with stage1 either: ``` $ zig run a.zig -fstage1 ./lib/std/start.zig:571:17: error: expected return type of main to be 'void', '!void', 'noreturn', 'u8', or '!u8' @compileError(bad_main_ret);...

`Reader.readStruct` has not been updated since before packed structs became integer backed, the assertion should be changed to explicitly check for `.Extern` layout.

Duplicate of #20765

This looks like it fixes #19656 and #19594, can you confirm?