Building for PICO_BOARD=pico2 fails

[ndabas]

Edit: I first tried this on Windows but this is also failing on Linux platforms. So not a Windows-specific issue. It's the same error on Linux too.

---

I've tried with my own DIY toolchain and the official VS Code extension. Building pico-examples with pico2 as the target board fails at the end of the CMake configure process:

[cmake] -- Configuring done (4.5s)
[cmake] -- Generating done (3.2s)
[cmake] CMake Error:
[cmake]   Running
[cmake] 
[cmake]    'C:/Users/WDAGUtilityAccount/.pico-sdk/ninja/v1.12.1/ninja.exe' '-C' 'C:/Users/WDAGUtilityAccount/Downloads/pico-examples/build' '-t' 'recompact'
[cmake] 
[cmake]   failed with:
[cmake] 
[cmake]    ninja: warning: phony target 'bootloaders/encrypted/enc_bootloader.ld' names itself as an input; ignoring [-w phonycycle=warn]
[cmake] 
[cmake]   ninja: warning: phony target 'bootloaders/encrypted/hello_serial_enc.ld'
[cmake]   names itself as an input; ignoring [-w phonycycle=warn]
[cmake] 
[cmake]   ninja: error: build.ninja:11266: multiple rules generate
[cmake]   bootloaders/encrypted/enc_bootloader.ld
[cmake] 
[cmake]   
[cmake] 
[cmake] 
[cmake] 
[cmake] CMake Generate step failed.  Build files cannot be regenerated correctly.

I tried with CMake 3.28 and also 3.30, same result.

[matsobdev]

Same here (CMake 3.19.8), but for RISC-V Embedded (riscv32-unknown-elf) on Windows 7 SP1 x64 finishes mostly ok:

In function 'ip_reass_dequeue_datagram',
    inlined from 'ip4_reass' at E:/Download/Pico_2/pico-sdk-2.0.0/lib/lwip/src/core/ipv4/ip4_frag.c:663:5:
E:/Download/Pico_2/pico-sdk-2.0.0/lib/lwip/src/core/ipv4/ip4_frag.c:326:16: warning: potential null pointer dereference [-Wnull-dereference]
  326 |     prev->next = ipr->next;
      |     ~~~~~~~~~~~^~~~~~~~~~~
In function 'ip_reass_dequeue_datagram',
    inlined from 'ip4_reass' at E:/Download/Pico_2/pico-sdk-2.0.0/lib/lwip/src/core/ipv4/ip4_frag.c:684:5:
E:/Download/Pico_2/pico-sdk-2.0.0/lib/lwip/src/core/ipv4/ip4_frag.c:326:16: warning: null pointer dereference [-Wnull-dereference]
  326 |     prev->next = ipr->next;
      |     ~~~~~~~~~~~^~~~~~~~~~~

but "it's only a glitch".

[ndabas]

@matsobdev that looks like a completely separate issue. Would be good to create a new issue, because like I clarified, the problem I see is not specific to Windows.

[lurch]

Edit: I first tried this on Windows but this is also failing on Linux platforms. So not a Windows-specific issue. It's the same error on Linux too.

Looks like it might be specific to Ninja?

On Ubuntu 24.04 if I run cmake with:

cmake .. -DPICO_SDK_PATH=../../pico-sdk -DPICO_BOARD=pico2

then cmake completes successfully, and running make (eventually) completes successfully too. But if I create a separate build-directory and invoke cmake with:

cmake .. -DPICO_SDK_PATH=../../pico-sdk -DPICO_BOARD=pico2 -GNinja

then I get exactly the same error as you do above about multiple rules generate bootloaders/encrypted/enc_bootloader.ld :confused: I'm running cmake 3.22.1 and ninja 1.10.1

Ahhh.... but if I create yet another build directory and run:

cmake .. -DPICO_SDK_PATH=../../pico-sdk -DPICO_BOARD=pico -GNinja

then this time cmake completes successfully, and running ninja builds all the examples. So looks like there's something specific about the linker scripts for RP2350 that Ninja doesn't like, but Make is perfectly happy with?

[ndabas]

Yes, true:

• Generating Makefiles and building with make works fine for all targets;
• Building my own projects with PICO_BOARD=pico2 works fine with both make and ninja;
• Building pico-examples with Ninja and PICO_BOARD=pico2 fails.

The build.ninja contains these two definitions to build the target in question:

#############################################
# Utility command for enc_bootloader.ld

build bootloaders/encrypted/enc_bootloader.ld: phony bootloaders/encrypted/CMakeFiles/enc_bootloader.ld bootloaders/encrypted/enc_bootloader.ld

#############################################
# Custom command for bootloaders\encrypted\enc_bootloader.ld

build bootloaders/encrypted/enc_bootloader.ld | ${cmake_ninja_workdir}bootloaders/encrypted/enc_bootloader.ld: CUSTOM_COMMAND C$:/Program$ Files/Raspberry$ Pi/Pico$ SDK$ v2.0.0/pico-sdk/src/rp2_common/pico_crt0/rp2350/memmap_no_flash.ld
  COMMAND = C:\Windows\system32\cmd.exe /C "cd /D C:\Users\WDAGUtilityAccount\Documents\Pico-v2.0.0\pico-examples\build-pico2\bootloaders\encrypted && "C:\Program Files\Raspberry Pi\Pico SDK v2.0.0\cmake\bin\cmake.exe" "-DPICO_LINKER_SCRIPT_PATH:PATH=C:/Program Files/Raspberry Pi/Pico SDK v2.0.0/pico-sdk/src/rp2_common/pico_crt0/rp2350" -Dorigin="0x20070000" -Dlength="64k" -Doutput_file:FILEPATH=C:/Users/WDAGUtilityAccount/Documents/Pico-v2.0.0/pico-examples/build-pico2/bootloaders/encrypted/enc_bootloader.ld -P C:/Users/WDAGUtilityAccount/Documents/Pico-v2.0.0/pico-examples/build-pico2/bootloaders/encrypted/make_linker_script.cmake"
  DESC = Generating enc_bootloader.ld
  restat = 1

I guess these are generated by these lines in the source: https://github.com/raspberrypi/pico-examples/blob/7fe60d6b4027771e45d97f207532c41b1d8c5418/bootloaders/encrypted/CMakeLists.txt#L33 https://github.com/raspberrypi/pico-examples/blob/7fe60d6b4027771e45d97f207532c41b1d8c5418/bootloaders/encrypted/CMakeLists.txt#L26

I'm not really sure if this is a bug in CMake's Ninja generator, but it is a problem for building these examples on Windows, if I don't want to use nmake from Visual Studio or similar. Ninja is just a lot faster + easier to install.

[will-v-pi]

This should be fixed with that commit - literally just needed . changed to _ in the target name…

[kilograham]

fixed in develop

[ndabas]

@will-v-pi @kilograham great, thanks!