uclibc-compat: split .so and .a to fix segfault from symbol interposition#2000
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uclibc-compat: split .so and .a to fix segfault from symbol interposition#2000
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libuclibc-compat.so was exporting stat/mmap which overrode musl's implementations for ALL code in the process, including musl's own internal calls. This caused segfaults because musl expects 64-bit off_t but the shim's mmap takes uint32_t. Split into two libraries: - libuclibc-compat.so: only symbols MISSING from musl (__ctype_b, __assert, __fgetc_unlocked, memcpy_s, etc). Safe as shared lib. - libuclibc-compat-static.a: stat/mmap wrappers with uclibc-compatible ABI. Must be statically linked into the executable so overrides only affect vendor .so lookups through the executable's symbol scope. BUNDLE_SDK now builds and includes both in the toolchain tarball. Fixes: segfault in majestic on hi3516cv100 at hisi_free_mem_ex (mmap) Ref: #1992 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Problem
libuclibc-compat.soexportedstat/mmapwhich overrode musl's implementations process-wide, causing segfaults. musl expects 64-bitoff_tfor mmap but the shim's version takesuint32_t— when musl's own internal code called mmap, it hit the wrong implementation.Confirmed crash: majestic segfaults at
hisi_free_mem_ex(MMZ memory allocation via mmap) on hi3516cv100 nightly build.Fix
Split into two libraries:
libuclibc-compat.so: only symbols MISSING from musl (__ctype_b,__assert,__fgetc_unlocked,memcpy_s, etc). Safe as shared lib — no conflict.libuclibc-compat-static.a:stat/mmapwrappers. Must be statically linked into the executable, so overrides only affect vendor.solookups through the executable's symbol scope, not musl internally.BUNDLE_SDKupdated to build and include both in the toolchain tarball.Test plan
.sohas no stat/mmap,.ahas them-luclibc-compat(dynamic) +-luclibc-compat-static(static)Ref: #1992