https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90153
Bug ID: 90153
Summary: aarch64: unclear diagnostic for stack-protector
options
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: roland.illig at gmx dot de
Target Milestone: ---
From aarch64.c:
if (aarch64_stack_protector_guard == SSP_SYSREG
&& !(opts->x_aarch64_stack_protector_guard_offset_str
&& opts->x_aarch64_stack_protector_guard_reg_str))
{
error ("both %<-mstack-protector-guard-offset%> and "
"%<-mstack-protector-guard-reg%> must be used "
"with %<-mstack-protector-guard=sysreg%>");
}
From reading the diagnostic alone, it could also mean:
-mstack-protector-guard-offset requires -mstack-protector-guard=sysreg
and
-mstack-protector-guard-reg requires -mstack-protector-guard=sysreg
actually it's the other way round:
mstack-protector-guard=sysreg requires both mstack-protector-guard-offset and
mstack-protector-guard-reg to be set.
The term "must be used with" is ambiguous regarding the direction of the "must
be used" here. It could mean "from right to left", or alternatively, "from left
to right".
