Hey,  I have a project that requires the use of the ULP coprocessor in the ESP32S3.  Currently tested by creating a new project from the ulp-example in idf v4.3.2.
I started off by reading this post from a couple years ago: Topic: ESP32 with ULP support | Sysprogs

I checked to see that the toolchains are contained in the proper location and that the toolchains.xml has the paths in <AdditionalPathDirs> section.

Upon building the sample project, it fails at:
No CMAKE_ASM_COMPILER could be found.
No CMAKE_C_COMPILER could be found.

Going through the the cmakelists where  ulp_embed_binary(${ulp_app_name} “${ulp_s_sources}” “${ulp_exp_dep_srcs}”) is being called, there was a section missing for the esp32s3 target. I added that and used the s2 toolchain as the documentation said they are the same. (if(IDF_TARGET STREQUAL “esp32s3”))

I then followed and confirmed that those things it was complaining about were being set in this file by using the cmake debugger:  (set(TOOLCHAIN_FLAG ${idf_path}/components/ulp/cmake/toolchain-esp32s2-ulp.cmake))

set(CMAKE_C_COMPILER “xtensa-esp32s2-elf-gcc”)
set(CMAKE_ASM_COMPILER “esp32s2ulp-elf-as”)

Unfortunately, that did not solve my issue. I then tried with esp32s2 and same situation.

Maybe it has something to do with those two cmake variables being added to a toolchain flag that is then passed as an argument to a cmake externalproject_add call. (-DCMAKE_TOOLCHAIN_FILE=${TOOLCHAIN_FLAG})

Any clue what I may be doing wrong? Thanks.