fix build and include guard. #1834

Job	Run time
clang-sanitizers (,thread)	2m 45s
clang-sanitizers (,address,undefined)	2m 19s
linux-compat (manylinux1-x64)	1m 31s
downstream	28m 13s
linux-compat (manylinux1-x86)	1m 40s
linux-compiler-compat (clang-3)	2m 10s
linux-compat (manylinux2014-x64)	1m 54s
linux-compiler-compat (clang-6)	4m 15s
linux-compat (manylinux2014-x86)	1m 40s
linux-compiler-compat (clang-8)	4m 43s
linux-shared-libs	1m 52s
linux-compat (raspbian-bullseye)	13m 21s
linux-compiler-compat (clang-9)	4m 42s
linux-compat (fedora-34-x64)	1m 45s
linux-no-cpu-extensions	1m 52s
linux-compiler-compat (clang-10)	2m 11s
linux-compat (opensuse-leap)	2m 1s
linux-compiler-compat (clang-11)	2m 25s
linux-compiler-compat (gcc-4.8)	1m 30s
linux-compat (rhel8-x64)	1m 39s
windows	3m 9s
linux-compiler-compat (gcc-5)	2m 23s
linux-compat (al2-x64)	1m 37s
linux-compiler-compat (gcc-6)	1m 48s
windows-app-verifier	2m 35s
linux-compiler-compat (gcc-7)	1m 56s
windows-no-cpu-extensions	3m 24s
linux-compiler-compat (gcc-8)	2m 1s
windows-shared-libs	2m 4s
linux-compiler-compat (gcc-11)	2m 42s
windows-vc14 (x86)	1m 37s
windows-vc14 (x64)	1m 41s
windows-vc15 (x86)	2m 11s
windows-vc15 (x64)	2m 10s
windows-vc16 (x86)	3m 23s
windows-vc16 (x64)	3m 24s
Cross Compile linux-armv6	2m 35s
openbsd	16m 31s
Cross Compile linux-armv7	2m 13s
osx	2m 39s
osx-no-cpu-extensions	2m 44s
Cross Compile linux-arm64	2m 16s
Cross Compile android-armv7	3m 45s
linux-debug	1m 39s
osx-debug	3m 16s
windows-debug	3m 22s
	2h 43m 33s

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