Determining if the function fopen_s exists failed with the following output:
Change Dir: /tmp/instance-1/output-1/build/piglit-2affee53f3ad7a96f5b397a2b6d6408af8a374b0/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/make cmTC_63df4/fast && make[1]: Entering directory '/tmp/instance-1/output-1/build/piglit-2affee53f3ad7a96f5b397a2b6d6408af8a374b0/CMakeFiles/CMakeTmp'
/usr/bin/make -f CMakeFiles/cmTC_63df4.dir/build.make CMakeFiles/cmTC_63df4.dir/build
make[2]: Entering directory '/tmp/instance-1/output-1/build/piglit-2affee53f3ad7a96f5b397a2b6d6408af8a374b0/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_63df4.dir/CheckFunctionExists.c.o
/tmp/instance-1/output-1/host/bin/mipsel-linux-gcc --sysroot=/tmp/instance-1/output-1/host/mipsel-buildroot-linux-gnu/sysroot   -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -g0 -D_FORTIFY_SOURCE=1 -Wall -std=gnu99 -Werror=vla -Werror=pointer-arith -Werror=variadic-macros -DCHECK_FUNCTION_EXISTS=fopen_s  -DNDEBUG   -o CMakeFiles/cmTC_63df4.dir/CheckFunctionExists.c.o   -c /usr/share/cmake-3.16/Modules/CheckFunctionExists.c
Linking C executable cmTC_63df4
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_63df4.dir/link.txt --verbose=1
/tmp/instance-1/output-1/host/bin/mipsel-linux-gcc --sysroot=/tmp/instance-1/output-1/host/mipsel-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -g0 -D_FORTIFY_SOURCE=1 -Wall -std=gnu99 -Werror=vla -Werror=pointer-arith -Werror=variadic-macros -DCHECK_FUNCTION_EXISTS=fopen_s  -DNDEBUG    CMakeFiles/cmTC_63df4.dir/CheckFunctionExists.c.o  -o cmTC_63df4 
/tmp/instance-1/output-1/host/opt/ext-toolchain/bin/../lib/gcc/mipsel-buildroot-linux-gnu/10.3.0/../../../../mipsel-buildroot-linux-gnu/bin/ld: CMakeFiles/cmTC_63df4.dir/CheckFunctionExists.c.o: in function `main':
CheckFunctionExists.c:(.text.startup+0xc): undefined reference to `fopen_s'
/tmp/instance-1/output-1/host/opt/ext-toolchain/bin/../lib/gcc/mipsel-buildroot-linux-gnu/10.3.0/../../../../mipsel-buildroot-linux-gnu/bin/ld: CheckFunctionExists.c:(.text.startup+0x28): undefined reference to `fopen_s'
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/cmTC_63df4.dir/build.make:87: cmTC_63df4] Error 1
make[2]: Leaving directory '/tmp/instance-1/output-1/build/piglit-2affee53f3ad7a96f5b397a2b6d6408af8a374b0/CMakeFiles/CMakeTmp'
make[1]: *** [Makefile:121: cmTC_63df4/fast] Error 2
make[1]: Leaving directory '/tmp/instance-1/output-1/build/piglit-2affee53f3ad7a96f5b397a2b6d6408af8a374b0/CMakeFiles/CMakeTmp'