SAL: Explicitly allocate sht variable in SAL_CS#627
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For reasons not entirely clear, deallocation of the RK2 control structure caused a segmentation fault when compiled by Nvidia. A deeper investigation suggested that the compiler was attempting to deallocate a nullified pointer during automatic cleanup of RK2->SAL->sht. Apparently deallocation of a NULL pointer is an error (even though free() is not supposed to care). By redefining `sht` as an allocatable component rather than a local component of the SAL_CS instance, it seemed to satisfy the compiler that nothing was needed and the error went away. There are still some lingering questions behind the cause of the segfault, but for now I am going to put this under "compiler bug". This patch also initializes some of the logical flags in the SAL_CS type. This is possibly unnecessary, but it is consistent with the general rules of safety followed in other MOM6 derived types.
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The issue appears to be resolved: https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/jobs/127658 |
adcroft
approved these changes
May 13, 2024
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Gaea regression: https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/pipelines/23449 ✔️ (And no silent Nvidia errors: https://gitlab.gfdl.noaa.gov/ogrp/MOM6/-/jobs/127853/raw) |
This was referenced May 16, 2024
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For reasons not entirely clear, deallocation of the RK2 control structure caused a segmentation fault when compiled by Nvidia. A deeper investigation suggested that the compiler was attempting to deallocate a nullified pointer during automatic cleanup of RK2->SAL->sht. Apparently deallocation of a NULL pointer is an error (even though free() is not supposed to care).
By redefining
shtas an allocatable component rather than a local component of the SAL_CS instance, it seemed to satisfy the compiler that nothing was needed and the error went away.There are still some lingering questions behind the cause of the segfault, but for now I am going to put this under "compiler bug".
This patch also initializes some of the logical flags in the SAL_CS type. This is possibly unnecessary, but it is consistent with the general rules of safety followed in other MOM6 derived types.