On Friday, 10 October 2025 at 09:14:15 UTC, felixfxu wrote:
and compile them by:
`dmd source/app.d source/importctest.c` OK
`ldc2 source/app.d source/importctest.c` OK,
but with gdc:
gdc source/app.d source/importctest.c
source/app.d:2:8: error: unable to read module ‘importctest’
gdc doesn't compile C files, rather it delegates the compilation
to gcc-proper in a separate compilation unit.
What you're running is equivalent to:
```bash
gdc -c source/app.d
gcc -c source/importctest.c
gdc source/app.o source/importctest.o
```
Therefore, the D module needs to be told where to find the source
files, with `-I source`
Mind that C sources need to be preprocessed before handing them
over to the D compilation unit.
https://gcc.gnu.org/onlinedocs/gdc/ImportC.html
