2015Q4 newlib nano for ARMv5TE uses Thumb-2 instructions

After upgrading to 5.2 2015Q4 from 4.9 2015Q3, I encountered an undefined instruction exception on my ARM968E-S (NXP LPC2929). I investigated and found that the default newlib nano (arm-none-eabi/lib/libc_nano.a) contains a Thumb-2 instruction in strlen, specifically ldrb.w. Thumb-2 is not supported on architectures before ARMv6T2, so this crashes. Using objdump -d on the library:

<other object files>

lib_a-strlen.o: file format elf32-littlearm

Disassembly of section .text:

00000000 <strlen>:
   0: 4603 mov r3, r0
   2: f813 2b01 ldrb.w r2, [r3], #1
   6: 2a00 cmp r2, #0
   8: d1fb bne.n 2 <strlen+0x2>
   a: 1a18 subs r0, r3, r0
   c: 3801 subs r0, #1
   e: 4770 bx lr

<other object files>

This makes it into my final executable, and the CPU never gets past <strlen+2>. It appears from a quick regex search of the objdump output that there are no other functions using Thumb instructions, so perhaps this was a hand-coded assembly function?

I'm using the prebuilt Win32 toolchain from Launchpad, host OS Windows 10 Pro. My final link command is:
arm-none-eabi-g++ -g -Og -mcpu=arm968e-s -march=armv5te --specs=nano.specs -nostartfiles -Wl,--gc-sections -Tboard/cs2.ld -Wl,-Map=main/default.elf.map main/Application.o main/PowertrainApplication.o main/default.o libScreens.a libTextDisplay.a libTransmission.a libVariation.a libOption.a libSensor.a libShiftSelector.a libControl.a libNet.a libCAN.a libDiag.a libParam.a libHardware.a libCore.a libBoard.a -o main/default.elf
I would expect this to produce a binary with only ARM and Thumb (not Thumb-2) instructions. Using the 2015Q3 release, for example, strlen is all in ARM mode.