I updated to (via a cross build from amd64 that was based on -march=armv7-a -mcpu=cortex-a7): # freebsd-version -ku; uname -aKU 11.0-CURRENT 11.0-CURRENT FreeBSD rpi2 11.0-CURRENT FreeBSD 11.0-CURRENT #8 r293129M: Sun Jan 3 20:37:26 PST 2016 root@FreeBSDx64:/usr/obj/clang/arm.armv6/usr/src/sys/RPI2-NODBG arm 1100093 1100093 on an rpi2b in order to pick up and try out: BEGIN -r292964 description Author: ian Date: Wed Dec 30 23:04:08 2015 New Revision: 292964 URL: https://svnweb.freebsd.org/changeset/base/292964 Log: Add the MOVT/MOVW types to the list of relocs which do not generate .plt entries. This fixes the segfaults in arm userland code compiled with -march= or -mcpu= values that allow the compiler to generate movw/movt sequences to load 32-bit constants. Modified: head/contrib/binutils/bfd/elf32-arm.c END -r292964 description instead of using /usr/local/arm-gnueabi-freebsd/bin/* binutils as I have been experimenting with. I tried something simple and C-based on the rpi2: portmaster -DK textproc/expat2 based on: # more /etc/make.conf DEFAULT_VERSIONS+=perl5=5.22 WRKDIRPREFIX=/usr/obj/portswork WITH_DEBUG= WITH_DEBUG_FILES= MALLOC_PRODUCTION= TO_TYPE=armv6 TOOLS_TO_TYPE=arm-gnueabi VERSION_CONTEXT=11.0 .if ${.MAKE.LEVEL} == 0 CC=/usr/bin/clang -v -target ${TO_TYPE}--freebsd${VERSION_CONTEXT}-gnueabi -march=armv7-a -mcpu=cortex-a7 -mfloat-abi=softfp -mno-unaligned-access CXX=/usr/bin/clang++ -v -target ${TO_TYPE}--freebsd${VERSION_CONTEXT}-gnueabi -march=armv7-a -mcpu=cortex-a7 -mfloat-abi=softfp -mno-unaligned-access CPP=/usr/bin/clang-cpp -v -target ${TO_TYPE}--freebsd${VERSION_CONTEXT}-gnueabi -march=armv7-a -mcpu=cortex-a7 -mfloat-abi=softfp -mno-unaligned-access .export CC .export CXX .export CPP .endif (Note the -v's that show extra context during the command executions.) The failing result involving movw was "unresolvable R_ARM_MOVW_ABS_NC relocation against symbol `malloc@@FBSD_1.0'": /bin/sh ./libtool --silent --mode=link /usr/bin/clang -v -target armv6--freebsd11.0-gnueabi -march=armv7-a -mcpu=cortex-a7 -mfloat-abi=softfp -mno-unaligned-access -I./lib -I. -pipe -mfloat-abi=softfp -g -fno-strict-aliasing -Wall -Wmissing-prototypes -Wstrict-prototypes -fexceptions -DHAVE_EXPAT_CONFIG_H -no-undefined -version-info 7:0:6 -rpath /usr/local/lib -o libexpat.la lib/xmlparse.lo lib/xmltok.lo lib/xmlrole.lo FreeBSD clang version 3.7.1 (tags/RELEASE_371/final 255217) 20151225 Target: armv6--freebsd11.0-gnueabi Thread model: posix "/usr/bin/ld" --eh-frame-hdr -Bshareable --hash-style=both --enable-new-dtags -o .libs/libexpat.so.1.6.0 /usr/lib/crti.o /usr/lib/crtbeginS.o -L/usr/lib lib/.libs/xmlparse.o lib/.libs/xmltok.o lib/.libs/xmlrole.o -soname libexpat.so.1 -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/crtendS.o /usr/lib/crtn.o /usr/bin/ld: lib/.libs/xmlparse.o(.text+0x198): unresolvable R_ARM_MOVW_ABS_NC relocation against symbol `malloc@@FBSD_1.0' /usr/bin/ld: final link failed: Nonrepresentable section on output clang: error: linker command failed with exit code 1 (use -v to see invocation) *** Error code 1 Stop. make[1]: stopped in /usr/obj/portswork/usr/ports/textproc/expat2/work/expat-2.1.0 *** Error code 1 For reference: here is one of the prior C compiles (xmlparse.c -> xmlparse.o as referenced in the failure): /bin/sh ./libtool --silent --mode=compile /usr/bin/clang -v -target armv6--freebsd11.0-gnueabi -march=armv7-a -mcpu=cortex-a7 -mfloat-abi=softfp -mno-unaligned-access -I./lib -I. -pipe -mfloat-abi=softfp -g -fno-strict-aliasing -Wall -Wmissing-prototypes -Wstrict-prototypes -fexceptions -DHAVE_EXPAT_CONFIG_H -o lib/xmlparse.lo -c lib/xmlparse.c FreeBSD clang version 3.7.1 (tags/RELEASE_371/final 255217) 20151225 Target: armv6--freebsd11.0-gnueabi Thread model: posix "/usr/bin/clang" -cc1 -triple armv7--freebsd11.0-gnueabi -emit-obj -mrelax-all -disable-free -main-file-name xmlparse.c -mrelocation-model static -mthread-model posix -mdisable-fp-elim -relaxed-aliasing -masm-verbose -mconstructor-aliases -target-cpu cortex-a7 -target-feature +soft-float-abi -target-abi aapcs-linux -mfloat-abi soft -backend-option -arm-strict-align -v -gdwarf-2 -dwarf-column-info -coverage-file /usr/obj/portswork/usr/ports/textproc/expat2/work/expat-2.1.0/xmlparse.c -resource-dir /usr/bin/../lib/clang/3.7.1 -D HAVE_EXPAT_CONFIG_H -I ./lib -I . -Wall -Wmissing-prototypes -Wstrict-prototypes -fdebug-compilation-dir /usr/obj/portswork/usr/ports/textproc/expat2/work/expat-2.1.0 -ferror-limit 19 -fmessage-length 200 -mstackrealign -fno-signed-char -fobjc-runtime=gnustep -fexceptions -fdiagnostics-show-option -fcolor-diagnostics -o xmlparse.o -x c lib/xmlparse.c clang -cc1 version 3.7.1 based upon LLVM 3.7.1 default target armv6--freebsd11.0-gnueabi #include "..." search starts here: #include <...> search starts here: ./lib . /usr/bin/../lib/clang/3.7.1/include /usr/include End of search list.
Investigating the issue I had the portmaster activity use the /usr/local/arm-gnueabi-freebsd/bin/ tools instead (via /etc/make.conf changes) and in that context the message is different but it was still an error: relocation R_ARM_MOVW_ABS_NC against `malloc' can not be used when making a shared object; recompile with -fPIC Trying again with -fPIC does let the portmaster command complete in this /usr/local/arm-gnueabi-freebsd/bin/ based tool context. Going back and trying -fPIC in the /usr/bin/ based tools context also lets the portmaster command complete. (That context without -fPIC did not directly indicate to try -fPIC in its messages.) So maybe part of the issue is having compiler arguments like -fPIC show up in commands for contexts like -march=armv7-a -mcpu=cortex-a7 without manual intervention in each case. For ports: some parts of a more complicated port might needed such and other parts might not. FYI: The detailed /usr/local/arm-gnueabi-freebsd/bin/ld invocation that reported that other error mentioning -fPIC was: /bin/sh ./libtool --silent --mode=link /usr/bin/clang -v -target armv6--freebsd11.0-gnueabi -march=armv7-a -mcpu=cortex-a7 -mfloat-abi=softfp -mno-unaligned-access -B/usr/local/arm-gnueabi-freebsd/bin -I./lib -I. -pipe -mfloat-abi=softfp -g -fno-strict-aliasing -Wall -Wmissing-prototypes -Wstrict-prototypes -fexceptions -DHAVE_EXPAT_CONFIG_H -no-undefined -version-info 7:0:6 -rpath /usr/local/lib -o libexpat.la lib/xmlparse.lo lib/xmltok.lo lib/xmlrole.lo FreeBSD clang version 3.7.1 (tags/RELEASE_371/final 255217) 20151225 Target: armv6--freebsd11.0-gnueabi Thread model: posix "/usr/local/arm-gnueabi-freebsd/bin/ld" --eh-frame-hdr -Bshareable --hash-style=both --enable-new-dtags -o .libs/libexpat.so.1.6.0 /usr/lib/crti.o /usr/lib/crtbeginS.o -L/usr/lib lib/.libs/xmlparse.o lib/.libs/xmltok.o lib/.libs/xmlrole.o -soname libexpat.so.1 -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/crtendS.o /usr/lib/crtn.o /usr/local/arm-gnueabi-freebsd/bin/ld: lib/.libs/xmlparse.o: relocation R_ARM_MOVW_ABS_NC against `malloc' can not be used when making a shared object; recompile with -fPIC lib/.libs/xmlparse.o: error adding symbols: Bad value clang: error: linker command failed with exit code 1 (use -v to see invocation) *** Error code 1
Ian Lapore reports the correct interpretation of what I saw is that textproc/expat2 needs to be fixed for how it is built: All of this is a complex way of saying "there is a bug in the expat2 port" (that being that it tries to build a shared library from object files that were compiled without -fpic). Adding -fpic via make.conf is absolutely not a fix or even a marginally viable workaround. -- Ian
Looks like using -v on clang/clang++ command lines messes up autoconf/libtool figuring things out: I had -v in the $(CC) and $(CXX) text. The overall result was that -fpic/-fPIC and the like were not being used because of teh options being classified as not-available.