ABI: Changes to Fortran-related get/set routines - #7942
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* Implement MPI_Abi_get_fortran_booleans in the MPIR layer * Implement MPI_Abi_get_fortran_info in the MPIR layer * Support Fortran booleans of size 16 * Use MPI_ERR_ARG to signal bad logical_size * Do not expose MPIR_fortran_true/false as a visible symbol.
…essor * Allow for get/set Fortran booleans in arbitrary and thus possibly unaligned memory locations by using an intermediate value and memcpy. * Refactor repetitive code using C preprocessor macros.
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| intN_t true_value = (intN_t) MPIR_fortran_true; \ | ||
| intN_t false_value = (intN_t) MPIR_fortran_false; \ | ||
| (void) memcpy(logical_true, &true_value, sizeof(intN_t)); \ | ||
| (void) memcpy(logical_false, &false_value, sizeof(intN_t)); \ |
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Wait. We need consider endian to use memcpy
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What do you mean? The C compiler and the Fortran compiler would use the same endianness. The use of memcpy here preserves endianness. I'm using memcpy to avoid alignment issues, in case the user is trying to get/set the booleans from unaligned memory (e.g. members of a packed struct or something like that, or even maybe a byte array).
Am I missing something obvious?
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Pull Request Description
Changes to Fortran ABI get/set routines. Some bits may be controversial. this is a middle ground of my interpretation of the standard and what Open MPI has implemented (note: not by me). Split in two commits to help review, can be squashed.
Partially addresses #7938, remove symbol visibility
MPIR_fortran_true/falsefrom the MPI libraries.Commit messages pasted below for the reviewer convenience:
bindings/c/abi: Refactor bindings generation for Fortran APIs
bindings/c/abi: Implement Fortran get/set booleans with the C preprocessor
unaligned memory locations by using an intermediate value and memcpy.
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