Compilation for blackpill_f411ce ends in error openr.c:(.text._open_r+0x10): undefined reference to `_open'

[brightproject]

I am compiling the example code from

https://github.com/avpripri/RTIMULib2/tree/master/Arduino

Under esp32 the code is compiling and working perfectly.

[env:ESP32]
platform =
espressif32@^3.5.0
; espressif32@^6.7.0
; espressif32@^6.8.1
; https://github.com/pioarduino/platform-espressif32
board = esp32-s3-devkitc-1-n16r8
framework = arduino
monitor_speed = 115200
monitor_port = COM6
upload_speed = 921600
upload_port = COM6
monitor_filters = esp32_exception_decoder

For stm32 everything is much more interesting and confusing.

Processing genericSTM32F411CE (platform:
platformio/ststm32@^14.1.0; board: blackpill_f411ce; framework: arduino)
--------------------------------Verbose mode can be enabled via -v, --verbose option
CONFIGURATION: https://docs.platformio.org/page/boards/ststm32/blackpill_f411ce.html
PLATFORM: ST STM32 (14.2.0) > WeAct Studio BlackPill V2.0 (STM32F411CE)
HARDWARE: STM32F411CEU6 100MHz, 128KB RAM, 512KB Flash
DEBUG: Current (blackmagic) External (blackmagic, cmsis-dap, jlink, stlink)
PACKAGES:

• framework-arduinoststm32 @ 4.20000.210603 (2.0.0)
• framework-cmsis @ 2.50700.210515 (5.7.0)
• toolchain-gccarmnoneeabi @ 1.90201.191206 (9.2.1)
  Converting RTArduLinkIMU.ino

[platformio]
; default_envs = genericSTM32F103CB
default_envs = genericSTM32F411CE

[env:genericSTM32F103CB]
platform =
; ststm32@^6.1.1
; ststm32@^8.0.0
ststm32@^9.0.0
board = genericSTM32F103CB
framework = arduino
upload_protocol = serial

[env:genericSTM32F411CE]
platform =
; platformio/ststm32@^6.1.1
; platformio/ststm32@^8.0.0
; platformio/ststm32@^14.1.0
platformio/ststm32@^17.5.0
; platform_packages =
; platformio/[email protected]
board = blackpill_f411ce
framework = arduino

monitor_speed = 115200
; monitor_speed = 230400
monitor_port = COM6

; monitor_filters = default, time, log2file
monitor_filters = time, log2file

upload_protocol =
; serial
stlink
build_flags =
; -Q
; -lrt
-specs=nosys.specs
; -D SOME_MACRO=1
; -D CONFIG_STD_CPP17=1
; -D CONFIG_NEWLIB_LIBC=1
; -D NEWLIB=1
; -v
; -w
; -Werror

If I select board genericSTM32F103CB, and version platformio/ststm32@^6.1.1, then the code is compiled and everything is OK.
With newer versions the code does not compile.
If I select board genericSTM32F411CE, then the code is not compiled, neither with version 17.5.0 nor with the newest one.
The error is always like this:

.platformio/packages/toolchain-gccarmnoneeabi/bin/../lib/gcc/arm-none-eabi/12.3.1/../../../../arm-none-eabi/bin/ld.exe:

.platformio/packages/toolchain-gccarmnoneeabi/bin/../lib/gcc/arm-none-eabi/12.3.1/../../../../arm-none-eabi/lib/thumb/v7e-m+fp/hard\libc_nano.a(libc_a-openr.o): in function `_open_r':
openr.c:(.text._open_r+0x10): undefined reference to `_open'
collect2.exe: error: ld returned 1 exit status
*** [.pio\build\genericSTM32F411CE\firmware.elf] Error 1

note that I try to use flags:

build_flags = -specs=nosys.specs
But this does not lead to a positive result.
I'm also curious what the flag does -Q и how to output the compilation log if I want to output information with the -v or -Werror flag I just don't have enough terminal buffer.
Specifying in the *ini file

monitor_filters = default, time, log2file

Doesn't give any results.

I will hope for help from the community.

[valeros]

Hi @brightproject, the issue tracker in this repository is not the right place to ask project-specific questions. Anyway, v6.1.1 is 4 years old, there have been plenty of changes in both - the underlying frameworks and the ststm32 platform itself. First of all, I'd recommend using the latest version v17.x. Secondly, I doubt that build_flags = -specs=nosys.specs is the correct way of setting special linker flags, it should probably be passed to the linker via an extra script, see https://docs.platformio.org/en/latest/scripting/examples/extra_linker_flags.html

[brightproject]

Anyway, v6.1.1 is 4 years old

Thanks @valeros for the kind words and explanations.
That's the problem, with the latest version of the framework, I get similar compilation errors.
And I can't even figure out what the reason for this compiler behavior is.
If only I could find at least one clue, I would refactor the code for the new framework.

[brightproject]

The build for .pio is OK, the solution to the problem is here:

https://github.com/orgs/stm32duino/discussions/2523