https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80044
Bug ID: 80044
Summary: Specifying both -static and -pie insanity
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: driver
Assignee: unassigned at gcc dot gnu.org
Reporter: amodra at gmail dot com
Target Milestone: ---
-static and -pie are incompatible, yet gcc neither warns nor errors on the
combination. What's more, gcc's behaviour depends on whether gcc was built
with --enable-default-pie.
If gcc was built with --enable-default-pie then -static silently overrides an
explicit -pie, at least on x86 and I suspect most targets. -static is passed
on to ld, gcc specifies the static startup files, and no -dynamic-linker is
passed to ld. This is reasonable, but a warning that the explicit -pie was
overridden would be nicer.
If gcc was built with --disable-default-pie then -static does not fully
override -pie. On x86, you get the static startup files, no -dynamic-linker,
and both -static and -pie are passed on to the linker. ld.gold errors on that
combination. ld.bfd tries to generate a PIE using the static startup files and
static (typically non-pic) libraries, and typically the wrong ld.so. The wrong
ld.so leads to a somewhat cryptic "file not found" message on trying to run an
executable. Non-pic startup and libraries result in a linker error on x86_64,
and text relocations on powerpc64le. TEXTREL and ifunc as found in modern
glibc are fundamentally incompatible: When applying the text relocations, ld.so
makes the text segment temporarily writeable (and non-exec), but the text needs
to be exec to run ifunc resolvers. A segfault before main is the result.
