Migrating from -current to stable/12 on RPI2B (ARMv7)

[bob prohaska]

Having a bit of trouble migrating to stable/12 from 13.0-CURRENT 
FreeBSD 13.0-CURRENT #3 r368820: Sat Dec 26 19:01:50 PST 2020     
bob at www.zefox.com:/usr/obj/usr/src/arm.armv7/sys/GENERIC-MMCCAM  arm

This is on a Pi2B v1.1 The MMCCAM kernel option was added for sake 
of the experiment and hasn't, up to now, been accompanied by any
visible problems. World and kernel have been built many times, no
problems. 

Buildworld keeps stopping at
--- clang.full ---
c++ -O -pipe -fno-common -mlong-calls -I/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/clang/libclang -I/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/clang/libllvm -I/usr/freebsd-src/contrib/llvm-project/clang/include -I/usr/freebsd-src/lib/clang/include -I/usr/freebsd-src/contrib/llvm-project/llvm/include -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -DHAVE_VCS_VERSION_INC -DNDEBUG -DLLVM_DEFAULT_TARGET_TRIPLE=\"armv7-unknown-freebsd12.2-gnueabihf\" -DLLVM_HOST_TRIPLE=\"armv7-unknown-freebsd12.2\" -DDEFAULT_SYSROOT=\"/usr/obj/usr/freebsd-src/arm.armv7/tmp\" -DLLVM_TARGET_ENABLE_ARM -DLLVM_NATIVE_ASMPARSER=LLVMInitializeARMAsmParser -DLLVM_NATIVE_ASMPRINTER=LLVMInitializeARMAsmPrinter -DLLVM_NATIVE_DISASSEMBLER=LLVMInitializeARMDisassembler -DLLVM_NATIVE_TARGET=LLVMInitializeARMTarget -DLLVM_NATIVE_TARGETINFO=LLVMInitializeARMTargetInfo -DLLVM_NATIVE_TARGETMC=LLVMInitializeARMTargetMC -ffunction-sections -fdata-sections -gline-tables-only -Wno-format-zero-length -Qunused-arguments -I/usr/obj/usr/freebsd-src/arm.armv7/tmp/legacy/usr/include -fno-exceptions -fno-rtti -std=c++14 -stdlib=libc++ -Wno-c++11-extensions  -Wl,--gc-sections -static  -L/usr/obj/usr/freebsd-src/arm.armv7/tmp/legacy/usr/lib -o clang.full  cc1_main.o cc1as_main.o cc1gen_reproducer_main.o driver.o /usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/clang/libclang/libclang.a /usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/clang/libllvm/libllvm.a -L/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/libz -lz -L/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/libexecinfo -lexecinfo -L/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/libelf -lelf -L/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/ncurses/ncursesw -lncursesw -L/usr/obj/usr/freebsd-src/arm.armv7/tmp/obj-tools/lib/libthr -lpthread -legacy
ld: error: failed to open clang.full: Cannot allocate memory
c++: error: linker command failed with exit code 1 (use -v to see invocation)
*** [clang.full] Error code 1

make[4]: stopped in /usr/freebsd-src/usr.bin/clang/clang
1 error

The failure occurs many minutes after the log entry appears. 
No errors on the console, swap tops near half a gig. The 
stable/12 sources being compiled were obtained via git. The 
-current sources used to compile the running system were 
obtained using svnlite. 

I don't recall seeing this much swap used before by armv7, 
but that's the only notable oddity.  

The stable/12 sources have been updated every day for the 
past few in hopes the trouble might go away, the -current 
sources seem to be updated as far as svnlite goes. 

Any suggestions appreciated, thanks for reading

bob prohaska