• Anonymouse (21/21) Dec 20 2022 I'm trying to build my thing with gdc. It (now) compiles, but
• Paul Backus (12/14) Dec 20 2022 `-allinst` tells the compiler to generate code for all
• Anonymouse (22/30) Dec 22 2022 [...]
• Siarhei Siamashka (5/6) Dec 22 2022 If it links on Ubuntu, but not on Manjaro/Arch, then is it

Anonymouse <zorael gmail.com> writes:

I'm trying to build my thing with gdc. It (now) compiles, but 
fails to link on this Manjaro/Arch laptop with gdc 12.2.0.

```
/usr/bin/ld: /tmp/ccstWTAS.o: in function 
`_D3std6format8internal5write__T8getWidthTAyaZQoFNaNfQlZl':
/usr/lib/gcc/x86_64-pc-linux-gnu/12.2.0/include/d/std/format/in
ernal/write.d:3819: undefined reference to
`_D3std9algorithm9searching__T3allSQBg6format8internal5write__T8getWidthTAyaZQoFQhZ9__lambda2Z__TQCpTQBcZQCxMFNaNfQBpZb'
/usr/bin/ld: /tmp/ccstWTAS.o: in function 
`_D3std6format8internal5write__T8getWidthTAaZQnFNaNfQkZl':
/usr/lib/gcc/x86_64-pc-linux-gnu/12.2.0/include/d/std/format/in
ernal/write.d:3819: undefined reference to
`_D3std9algorithm9searching__T3allSQBg6format8internal5write__T8getWidthTAaZQnFQgZ9__lambda2Z__TQCoTQBbZQCwMFNaNfQBoZb'
[...]
```

A few lines like those covering half a screen, all of it of 
phobos.

What conventional wisdom I've picked up somewhere along the way 
says to use `-allinst` in cases like these, and after asking 
around on the Discord and finding out about gdc's equivalent 
`-fall-instantiations`, it now links on a different Ubuntu 
machine with gdc 12.1.0. No luck still with the laptop and its 
12.2.0, although the linker outputs fewer errors now.

What does `-allinst` even do and why does it seem to be 
insufficient here?

Paul Backus <snarwin gmail.com> writes:

On Tuesday, 20 December 2022 at 20:01:04 UTC, Anonymouse wrote:
 What does `-allinst` even do

`-allinst` tells the compiler to generate code for all 
instantiated templates, even if it thinks that code has already 
been generated in a different object file.

Why would the compiler think that? Sometimes, which templates get 
instantiated can depend on which flags the code is compiled with. 
If you compile your code with one set of flags, and link it 
against a library compiled with a different set of flags, then 
the different invocations of the compiler may disagree on which 
templates should end up in which object files.

 and why does it seem to be insufficient here?

Hard to say without more information. Are you compiling with 
`-preview=dip1000`? If not, does adding that flag fix the error?

Anonymouse <zorael gmail.com> writes:

On Tuesday, 20 December 2022 at 20:55:08 UTC, Paul Backus wrote:

Apologies for the late reply.

 On Tuesday, 20 December 2022 at 20:01:04 UTC, Anonymouse wrote:
 What does `-allinst` even do

 `-allinst` tells the compiler to generate code for all 
 instantiated templates, even if it thinks that code has already 
 been generated in a different object file.

[...]

I see. That makes sense. When things fail (requiring `-allinst`), 
is that a bug I should report or a fact of life to lament?

 and why does it seem to be insufficient here?

 Hard to say without more information. Are you compiling with 
 `-preview=dip1000`? If not, does adding that flag fix the error?

I'm not compiling with `dip1000`. Adding it just adds some extra 
lines to the top of the linker errors.

Full demangled non-`dip1000` error, slightly formatted for 
readability;

```
/usr/bin/ld: 
../../.dub/packages/requests-2.0.9/requests/.dub/build/[...]/librequests.a: in
function `pure  safe void std.format.internal.write.formatValueImpl!(void
delegate(scope const(char)[]) pure nothrow  safe, ulong,
char).formatValueImpl(ref void delegate(scope const(char)[]) pure nothrow
 safe, const(ulong), scope ref
const(std.format.spec.FormatSpec!(char).FormatSpec))':
/usr/lib/gcc/x86_64-pc-linux-gnu/12.2.0/include/d/std/format/i
ternal/write.d:171: undefined reference to `pure nothrow  nogc  trusted
const(char)[] std.format.internal.write.formatValueImpl!(void delegate(scope
const(char)[]) pure nothrow  safe, ulong, char).formatValueImpl(ref void
delegate(scope const(char)[]) pure nothrow  safe, const(ulong), scope ref
const(std.format.spec.FormatSpec!(char).FormatSpec)).__lambda5!(
long).__lambda5(ref ulong)'

/usr/bin/ld: 
../../.dub/packages/requests-2.0.9/requests/.dub/build/[...]/librequests.a: in
function `pure  safe immutable(char)[]
std.algorithm.searching.find!(std.algorithm.mutation.stripLeft
(immutable(char)[], char).stripLeft(immutable(char)[], char).__lambda3,
immutable(char)[]).find(immutable(char)[])':
/usr/lib/gcc/x86_64-pc-linux-gnu/12.2.0/include/d/std/algorit
m/searching.d:1858: undefined reference to `pure nothrow  nogc  safe bool
std.algorithm.mutation.stripLeft!(immutable(char)[],
char).stripLeft(immutable(char)[], char).__lambda3!(dchar).__lambda3(dchar)'

collect2: error: ld returned 1 exit status
Error gdc failed with exit code 1.
```

In this case it's even in an external dependency (`requests`), 
which compiles by itself but not when dub builds my thing with it.

I'm not sure what to do.

Siarhei Siamashka <siarhei.siamashka gmail.com> writes:

On Thursday, 22 December 2022 at 15:32:28 UTC, Anonymouse wrote:
 I'm not sure what to do.

If it links on Ubuntu, but not on Manjaro/Arch, then is it 
possible that the GDC package from Manjaro/Arch is somehow 
provided with a missing, misconfigured or broken Phobos library?

Maybe try to compile GDC from sources yourself?