[PATCH] aarch64: Accept PLT calls to __getauxval within libc.so

Florian Weimer fw@deneb.enyo.de
Tue May 12 10:34:57 GMT 2020


When using outline atomics (-moutline-atomics, the default for ARMv8-A
starting with GCC 10), libgcc contains an ELF constructor which calls
__getauxval.  This code is built outside of glibc, so none of its
internal PLT avoidance schemes can be applied to it.  This change
suppresses the elf/check-localplt failure.

-----
 sysdeps/unix/sysv/linux/aarch64/localplt.data | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sysdeps/unix/sysv/linux/aarch64/localplt.data b/sysdeps/unix/sysv/linux/aarch64/localplt.data
index 56f362d3a7..2c14b652ef 100644
--- a/sysdeps/unix/sysv/linux/aarch64/localplt.data
+++ b/sysdeps/unix/sysv/linux/aarch64/localplt.data
@@ -7,6 +7,9 @@ libc.so: malloc
 libc.so: memalign
 libc.so: realloc
 libm.so: matherr
+# If outline atomics are used, libgcc (built outside of glibc) may
+# call __getauxval using the PLT.
+libc.so: __getauxval ?
 # The dynamic loader needs __tls_get_addr for TLS.
 ld.so: __tls_get_addr
 # The TLS-enabled version of these functions is interposed from libc.so.


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