Workaround upstream FreeBSD issue #272992 #51114
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FreeBSD does not support looking up WEAK symbols in its libc via `dlsym` if you're using a library-specific handle. It will give you the empty stub in libc instead of, e.g., the strong implementation in ld-elf.so This fix and the one that was merged upstream are pretty conspicuously incomplete, since `dlsym`, `dladdr` and a ton of other symbols still have stubs with no trampoline in libc: https://cgit.freebsd.org/src/tree/lib/libc/gen/dlfcn.c?id=21a52f99440c9bec7679f3b0c5c9d888901c3694 Thankfully, this appears to be the only function that we directly `ccall` from Julia's Libdl so we can leave this fix incomplete for now.
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| // This is a workaround for FreeBSD <= 13.2 which do not have | ||
| // https://cgit.freebsd.org/src/commit/?id=21a52f99440c9bec7679f3b0c5c9d888901c3694 | ||
| // (See https://github.com/JuliaLang/julia/issues/50846) | ||
| if (strcmp(f_name, "dl_iterate_phdr") == 0) |
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This seems reasonable to me as a stopgap solution but I wonder if there's a way we can more directly query whether dl_iterate_phdr resolved to libc does the right thing so that we don't have to perform this check on every call.
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I expect this check is generally a lot cheaper than the dlsyms below, but thankfully the standard function/library pointer caching for ccall should mean we only do this once per call-site
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staticfloat
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The x86_64-linux-gnuassertrr failure is unrelated |
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ELF doesn't handle WEAK symbols dynamically the way it handles them statically. Looking up overloaded WEAK symbols via a library-specific handle will often give you the empty stub (in `libc.so.7` in this case) instead of the strong implementation elsewhere (`ld-elf.so.1` here). Even after the [upstream fix](https://cgit.freebsd.org/src/commit/?id=21a52f99440c9bec7679f3b0c5c9d888901c3694), `dlsym`, `dladdr` and a ton of other symbols still have stubs with no trampoline in FreeBSD's libc: https://cgit.freebsd.org/src/tree/lib/libc/gen/dlfcn.c?id=21a52f99440c9bec7679f3b0c5c9d888901c3694 Thankfully `dl_iterate_phdr` appears to be the only function that we directly `ccall` from Julia's Libdl so we can leave this fix incomplete for now. Resolves #50846. (cherry picked from commit c659011)
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Backported PRs: - [x] #48625 <!-- add replace(io, str, patterns...) --> - [x] #48387 <!-- Improve documentation of sort-related functions --> - [x] #48363 <!-- Revise sort.md and docstrings in sort.jl --> - [x] #48977 <!-- Update SparseArrays.jl stdlib for SuiteSparse 7 --> - [x] #50719 <!-- fix `CyclePadding(::DataType)` --> - [x] #50694 <!-- inference: permit recursive type traits --> - [x] #50860 <!-- Add `Base.get_extension` to docs/API --> - [x] #50594 <!-- Disallow non-index Integer types in isassigned --> - [x] #50802 <!-- Makes IntrusiveLinkedListSynchronized mutable to avoid allocation on poptask --> - [x] #50858 <!-- Add a `threadpool` parameter to `Channel` constructor --> - [x] #50874 <!-- Restrict COFF to a single thread when symbol count is high --> - [x] #50822 <!-- Add default method for setmodifiers! --> - [x] #50730 <!-- Fix integer overflow in `isapprox` --> - [x] #50850 <!-- Remove weird Rational dispatch and add pi functions to list --> - [x] #50809 <!-- Limit type-printing in MethodError --> - [x] #50915 <!-- Add note the `Task` about sticky bit --> - [x] #50929 <!-- when widening tuple types in tmerge, only widen the complex parts --> - [x] #50928 <!-- Bump JuliaSyntax to 0.4.6 --> - [x] #50959 <!-- Update libssh2 patches --> - [x] #50823 <!-- Make ranges more robust with unsigned indexes. --> - [x] #48542 <!-- Add docs on task-specific buffering using multithreading --> - [x] #50912 <!-- Separate foreign threads into a :foreign threadpool --> - [x] #51010 <!-- Add ORIGIN to SuiteSparse rpath on Linux/FreeBSD --> - [x] #50753 <!-- cat: remove unused promote_eltype methods that confuse inference --> - [x] #51027 <!-- Implement realloc accounting correctly --> - [x] #51019 <!-- fix a case of potentially use of undefined variable when handling error in distributed message processing --> - [x] #51039 <!-- Revert "Optimize findall(f, ::AbstractArray{Bool}) (#42202)" --> - [x] #51036 <!-- add missing invoke edge for nospecialize targets --> - [x] #51042 <!-- inference: fix return_type_tfunc modeling of concrete functions --> - [x] #51114 <!-- Workaround upstream FreeBSD issue #272992 --> - [x] #50892 <!-- Add `JL_DLLIMPORT` to `small_typeof` declaration --> - [x] #51154 <!-- broadcast: use recursion rather than ntuple to map over a tuple --> - [x] #51153 <!-- fix debug typo in "add missing invoke edge for nospecialize targets (#51036)" --> - [x] #51222 <!-- Check again if the tty is open inside the IO lock --> - [x] #51236 <!-- Add lock around uv_unref during init --> - [x] #51243 <!-- GMP: Gracefully handle more overflows. --> - [x] #51254 <!-- Ryu: make sure adding zeros does not overwrite trailing dot --> - [x] #51175 <!-- shorten stale_age for cachefile lock --> - [x] #51300 <!-- fix method definition error for bad vararg --> - [x] #51307 <!-- fix force-throw ctrl-C on Windows --> - [x] #51303 <!-- ensure revising structs is safe --> - [x] #51393 - [x] #51403 Need manual backport: - [x] #51009 <!-- fix #50562, regression in `in` of tuple of Symbols --> - [x] #51053 <!-- Bump Statistics stdlib --> - [x] #51013 <!-- fix #50709, type bound error due to free typevar in sparam env --> - [x] #51305 <!-- reduce test time for rounding and floatfuncs --> Contains multiple commits, manual intervention needed: - [ ] #50663 <!-- Fix Expr(:loopinfo) codegen --> - [ ] #51035 <!-- refactor GC scanning code to reflect jl_binding_t are now first class --> - [ ] #51092 <!-- inference: fix bad effects for recursion --> - [x] #51247 <!-- Check if malloc has succeeded before incrementing gc stats --> - [x] #51294 <!-- use LibGit2_jll for LibGit2 library --> Non-merged PRs with backport label: - [ ] #51132 <!-- Handle `AbstractQ` in concatenation --> - [x] #51029 <!-- testdefs: make sure that if a test set changes the active project, they change it back when they're done --> - [ ] #50919 <!-- Code loading: do the "skipping mtime check for stdlib" check regardless of the value of `ispath(f)` --> - [ ] #50824 <!-- Add some aliasing warnings to docstrings for mutating functions --> - [x] #50385 <!-- Precompile pidlocks: add to NEWS and docs --> - [ ] #49805 <!-- Limit TimeType subtraction to AbstractDateTime -->
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ELF doesn't handle WEAK symbols dynamically the way it handles them statically. Looking up overloaded WEAK symbols via a library-specific handle will often give you the empty stub (in `libc.so.7` in this case) instead of the strong implementation elsewhere (`ld-elf.so.1` here). Even after the [upstream fix](https://cgit.freebsd.org/src/commit/?id=21a52f99440c9bec7679f3b0c5c9d888901c3694), `dlsym`, `dladdr` and a ton of other symbols still have stubs with no trampoline in FreeBSD's libc: https://cgit.freebsd.org/src/tree/lib/libc/gen/dlfcn.c?id=21a52f99440c9bec7679f3b0c5c9d888901c3694 Thankfully `dl_iterate_phdr` appears to be the only function that we directly `ccall` from Julia's Libdl so we can leave this fix incomplete for now. Resolves #50846. (cherry picked from commit c659011)
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ELF doesn't handle WEAK symbols dynamically the way it handles them statically.
Looking up overloaded WEAK symbols via a library-specific handle will often give you the empty stub (in
libc.so.7in this case) instead of the strong implementation elsewhere (ld-elf.so.1here).Even after the upstream fix,
dlsym,dladdrand a ton of other symbols still have stubs with no trampoline in FreeBSD's libc:https://cgit.freebsd.org/src/tree/lib/libc/gen/dlfcn.c?id=21a52f99440c9bec7679f3b0c5c9d888901c3694 Thankfully
dl_iterate_phdrappears to be the only function that we directlyccallfrom Julia's Libdl so we can leave this fix incomplete for now.Resolves #50846.