fix: enable FFI_MMAP_EXEC_WRIT for DragonFly BSD#930
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atgreen merged 1 commit intolibffi:masterfrom Aug 2, 2025
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Similar to PR libffi#265 [1], we need to enable FFI_MMAP_EXEC_WRIT to use explicit write+exec mapping on DragonFly BSD. Without this fix, we were having segfaults with Meld [2]; it would crash with SIGSEGV after 5 diff operations. The crash was caused by it attempting to execute code from non-execute memory region. Moreover, if we set the `machdep.pmap_nx_enable=2` tunable (i.e., strict NX mode), Meld would crash upon the first diff operation. Fix the `configure.ac` script to enable `FFI_MMAP_EXEC_WRIT` for DragonFly BSD. In addition, add it to the supported platforms table. [1] libffi#265 [2] https://meldmerge.org/
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@atgreen, thank you! |
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Similar to PR #265 [1], we need to enable FFI_MMAP_EXEC_WRIT to use explicit write+exec mapping on DragonFly BSD.
Without this fix, we were having segfaults with Meld [2]; it would crash with SIGSEGV after 5 diff operations. The crash was caused by it attempting to execute code from non-execute memory region. Moreover, if we set the
machdep.pmap_nx_enable=2tunable (i.e., strict NX mode), Meld would crash upon the first diff operation.Fix the
configure.acscript to enableFFI_MMAP_EXEC_WRITfor DragonFly BSD. In addition, add it to the supported platforms table.[1] #265
[2] https://meldmerge.org/