Broken Ninja builds after reconfiguring with multio 2.7.0

[awnawab]

What happened?

If the feature MULTIO_OUTPUT_MANAGER is enabled, then ninja builds fail with the following error after reconfiguring:

[721/964] Generating Fortran dyndep file src/multiom/CMakeFiles/multiom-encoders.dir/Fortran.dd
ninja: build stopped: multiple rules generate module/multiom/grib2_encoder_mod.mod.

Make is unaffected, and clean builds with ninja work fine too. The ninja problem goes away if the output manager is disabled.

What are the steps to reproduce the bug?

Build once with ninja, reconfigure, then build again. Module versions are:

• cmake 3.25.2
• ninja 1.10.0
• ecbuild 3.12.0

The other dependencies are at the versions given in the 50r1 ifs bundle

Version

2.7.0

Platform (OS and architecture)

Atos AC

Relevant log output

Accompanying data

No response

Organisation

No response

[dsarmany]

Thank you @awnawab -- I can confirm that this is exactly the behaviour I experience on atos myself when building. It is relatively long-standing, but we hope to be able to look into it soon.

[stefaniereuter]

Found from Balthasar:
This is because the three targets multiom-core and multiom-encoders and multiom specify the same .mod directory. That in itself appears ok but there's a bit of mix-up in the encoder source lists, because

# encoders-base/CMakeLists.txt
set( MULTIOM_ENCODERS_BASE_SOURCES
  ${MULTIOM_ENCODERS_BASE_MAIN_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SOURCES}
  CACHE INTERNAL "List of all sources in operations directory"
)

# encoders/CMakeLists.txt
set( MULTIOM_ENCODERS_SOURCES
  ${MULTIOM_ENCODERS_MAIN_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SOURCES}
  CACHE INTERNAL "List of all sources in operations directory"
)

# encoder-grib2/CMakeLists.txt
# Collect source files in module2
set( MULTIOM_ENCODER_GRIB2_MAIN_SOURCES
  ${MULTIOM_ENCODERS_GRIB2_DIR}/grib2_encoder_mod.F90
)
set( MULTIOM_ENCODER_GRIB2_SOURCES
  ${MULTIOM_ENCODER_GRIB2_MAIN_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SECTION0_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SECTION1_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SECTION2_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SECTION3_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SECTION4_SOURCES}
  ${MULTIOM_ENCODER_GRIB2_SECTION5_SOURCES}
  CACHE INTERNAL "List of all sources in encoders directory"
)

MULTIOM_ENCODERS_BASE_SOURCES is used in multiom-core and MULTIOM_ENCODERS_SOURCES is used in multiom-encoders. So the grib2 files are compiled for two targets but then write to the same module directory