https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91879
Bug ID: 91879
Summary: DESTDIR support seems incomplete
Product: gcc
Version: 9.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: other
Assignee: unassigned at gcc dot gnu.org
Reporter: stsp at users dot sourceforge.net
Target Milestone: ---
Hello.
I tried to build gcc with non-empty DESTDIR.
It fails on libquadmath:
In file included from ../../../gnu/gcc-9.2.0/libquadmath/math/x2y2m1q.c:19:
../../../gnu/gcc-9.2.0/libquadmath/quadmath-imp.h:24:10: fatal error: errno.h:
No such file or directory
24 | #include <errno.h>
| ^~~~~
The problem is that the system headers are searched in a
prefix path that doesn't account for DESTDIR. This is because
of the explicit -isystem in the command line. I looked at a
build system and found that -isystem is built from the "tooldir"
variable of the configure script. So I made the following change
to confirm my findings:
--- configure.ac.old 2019-09-24 03:44:28.141779422 +0300
+++ configure.ac 2019-09-24 03:30:59.022308759 +0300
@@ -2572,7 +2572,7 @@
# Some systems (e.g., one of the i386-aix systems the gas testers are
# using) don't handle "\$" correctly, so don't use it here.
-tooldir='${exec_prefix}'/${target_noncanonical}
+tooldir='${DESTDIR}${exec_prefix}'/${target_noncanonical}
build_tooldir=${tooldir}
# Create a .gdbinit file which runs the one in srcdir
And with that change the build worked.
So I suppose this is a build system bug.
