I got a bit curios about nuttx so I tried compiling it to run with qemu
Some more info. https://acassis.wordpress.com/2018/01/04/running-nuttx-on-esp32-board/
git clone https://bitbucket.org/nuttx/tools
cd tools/kconfig-frontends/
./configure --enable-mconf --enable-nconf --disable-gconf --disable-qconf
git clone https://bitbucket.org/nuttx/nuttx.git nuttx
./tools/configure.sh esp32-core/nsh
#Try to enable debug symbols also
cd tools
//./configure.sh esp32-core/nsh ./configure.sh esp32-core/smp cd - make oldconfig . ./setenv.sh make
Before sourcing the setenv.sh file above, you should examine it and perform edits as necessary so that TOOLCHAIN_BIN is the correct path to the directory than holds your toolchain binaries.
Only got this output.
make[1]: Leaving directory /home/olas/nuttx/configs' make: the -C' option requires a non-empty string argument
Usage: make [options] [target] ...
See configs/esp32-core/README.txt for further instructions
cd .. git clone https://bitbucket.org/nuttx/apps.git cd nuttx Added, CONFIG_APPS_DIR = ../apps to Makefile.unix
/home/olas/esp/esp-idf/components/esptool_py/esptool/esptool.py --chip esp32 elf2image --flash_mode dio --flash_size 4MB -o ./nuttx2.bin nuttx