Failing build: https://build.chromium.org/p/chromium.fyi/builders/ClangToTLinux/builds/9133

Logs: https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.fyi%2FClangToTLinux%2F9133%2F%2B%2Frecipes%2Fsteps%2Fcompile%2F0%2Fstdout

Excerpt:
[6758/42636] CXX obj/third_party/ced/ced/compact_enc_det_hint_code.o
FAILED: obj/third_party/ced/ced/compact_enc_det_hint_code.o 
../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/third_party/ced/ced/compact_enc_det_hint_code.o.d -DCOMPILER_GCC -DHTML5_MODE -DV8_DEPRECATION_WARNINGS -DUSE_UDEV -DUSE_AURA=1 -DUSE_PANGO=1 -DUSE_CAIRO=1 -DUSE_GLIB=1 -DUSE_NSS_CERTS=1 -DUSE_X11=1 -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD -DSAFE_BROWSING_DB_LOCAL -DCHROMIUM_BUILD -DFIELDTRIAL_TESTING_ENABLED -DCR_CLANG_REVISION=\"313759\" -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -DCOMPONENT_BUILD -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -I../.. -Igen -I../../third_party/ced/src -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -funwind-tables -fPIC -pipe -B../../third_party/binutils/Linux_x64/Release/bin -pthread -fcolor-diagnostics -Xclang -mllvm -Xclang -instcombine-lower-dbg-declare=1 -m64 -march=x86-64 -O2 -fno-ident -fdata-sections -ffunction-sections -fomit-frame-pointer -g2 -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Werror -Wall -Wno-unused-variable -Wno-missing-field-initializers -Wno-unused-parameter -Wno-c++11-narrowing -Wno-covered-switch-default -Wno-unneeded-internal-declaration -Wno-inconsistent-missing-override -Wno-undefined-var-template -Wno-nonportable-include-path -Wno-address-of-packed-member -Wno-unused-lambda-capture -Wno-user-defined-warnings -Wno-enum-compare-switch -Wno-tautological-unsigned-zero-compare -Wno-null-pointer-arithmetic -Wno-unused-function -std=gnu++14 -fno-rtti -nostdinc++ -isystem../../buildtools/third_party/libc++/trunk/include -isystem../../buildtools/third_party/libc++abi/trunk/include --sysroot=../../build/linux/debian_jessie_amd64-sysroot -fno-exceptions -fvisibility-inlines-hidden -c ../../third_party/ced/src/compact_enc_det/compact_enc_det_hint_code.cc -o obj/third_party/ced/ced/compact_enc_det_hint_code.o
../../third_party/ced/src/compact_enc_det/compact_enc_det_hint_code.cc:85:11: error: comparison of unsigned enum expression < 0 is always false [-Werror,-Wtautological-unsigned-enum-zero-compare]
  if (enc < 0) {
      ~~~ ^ ~
1 error generated.