Change Details

Link rtld-elf with a special static build of libcompiler_rt without -fstack-protector (SSP). Compilers may emit calls to builtin functions, but because of rtld's special needs and the use of the linker flag -nostdlib, the compiler builtin functions are not linked as normal. This now links the builtin library but built in a way compatible with rtld-elf. Previously we had two different solutions. On some architectures, we were able to extract reimplementations of the necessary builtin functions from our special build of libc. On ARM, we linked libcompiler_rt, but didn't guarantee that it didn't use SSP. This is motivated by the same issue as D26199 and D27665, but should be a simpler solution that applies to all architectures. --- This patch applies on top of a revert of D27665, which would be committed conccurently.

Statically link rtld-elf with libcompiler_rt on all architectures so that we don't need to try to pick and choose the bits we need from it for each architecture (we now leave that to the linker). Compilers may emit calls to support functions in this library, but because of the use of the linker flag -nostdlib for rtld's special needs, the library is not linked as normal. Previously we had two different solutions. On some architectures, we were able to extract reimplementations of the necessary builtin functions from our special build of libc. On ARM, we just linked libcompiler_rt. This is motivated by the same issue as D26199 and D27665, but should be a simpler solution that applies to all architectures. --- This patch applies on top of a revert of D27665, which would be committed concurrently.

LStatically link rtld-elf with a special static build of libcompiler_rt withoutlibcompiler_rt on all architectures so -fstack-protector (SSP). Compilers may emit calls to builtin functions,that we don't need to try to pick and choose the bits we need from it but because of rtld's special needs and the use offor each architecture (we now leave that to the linker flag). Compilers may -nostdlibemit calls to support functions in this library, the compiler builtin functions are not linked as normal.but because of the use This nowof the links the builtin library but built in a way compatible wither flag -nostdlib for rtld's special needs, the library is rtld-elfnot linked as normal. Previously we had two different solutions. On some architectures, we were able to extract reimplementations of the necessary builtin functions from our special build of libc. On ARM, we just linked libcompiler_rt, but didn't guarantee that it didn't use SSP. This is motivated by the same issue as D26199 and D27665, but should be a simpler solution that applies to all architectures. --- This patch applies on top of a revert of D27665, which would be committed conccuurrently.