This patch emits assembler directives for PACBTI build attributes as defined by the ABI. gcc/ChangeLog: * config/arm/arm.c (arm_file_start): Emit EABI attributes for Tag_PAC_extension, Tag_BTI_extension, TAG_BTI_use, TAG_PACRET_use. gcc/testsuite/ChangeLog: * gcc.target/arm/acle/pacbti-m-predef-1.c: New test. * gcc.target/arm/acle/pacbti-m-predef-3: Likewise. * gcc.target/arm/acle/pacbti-m-predef-6.c: Likewise. * gcc.target/arm/acle/pacbti-m-predef-7.c: Likewise. Co-Authored-By: Tejas Belagod