Disabling IPV4 casing compilation error (IDFGH-12117)

[ShubhadaHarkut-eaton]

Answers checklist.

• I have read the documentation ESP-IDF Programming Guide and the issue is not addressed there.
• I have updated my IDF branch (master or release) to the latest version and checked that the issue is present there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

IDF version.

4.4

Operating System used.

Windows

How did you build your project?

Command line with Make

If you are using Windows, please specify command line type.

None

What is the expected behavior?

IPV6 working standalone with ipv4 support completly disabled

What is the actual behavior?

Disabling IVP4 and building the idf ethernet example code only with IPV6 support enabled leading to many compilation error
idf version used : 4.4
os : windows
ESP : ESP32-WROVER-B

disabling LWIP_IPV4 in opts.h and enabling LWIP_IPV6 in the same file along with other menuconfig configurations for rnabling IPV6

Steps to reproduce.

disabling LWIP_IPV4 in opts.h and enabling LWIP_IPV6 in the same file along with other menuconfig configurations for rnabling IPV6

Build or installation Logs.

Building C object esp-idf/esp_netif/CMakeFiles/__idf_esp_netif.dir/lwip/esp_netif_lwip_defaults.c.obj
FAILED: esp-idf/esp_netif/CMakeFiles/__idf_esp_netif.dir/lwip/esp_netif_lwip_defaults.c.obj
C:\Espressif\tools\xtensa-esp32-elf\esp-2021r2-patch2-8.4.0\xtensa-esp32-elf\bin\xtensa-esp32-elf-gcc.exe  -Iconfig -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_netif/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_netif/lwip -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_netif/private_include -IC:/Espressif/frameworks/esp-idf-v4.4/components/newlib/platform_include -IC:/Espressif/frameworks/esp-idf-v4.4/components/freertos/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/freertos/include/esp_additions/freertos -IC:/Espressif/frameworks/esp-idf-v4.4/components/freertos/port/xtensa/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/freertos/include/esp_additions -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_hw_support/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_hw_support/include/soc -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_hw_support/include/soc/esp32 -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_hw_support/port/esp32/. -IC:/Espressif/frameworks/esp-idf-v4.4/components/heap/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/log/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/lwip/include/apps -IC:/Espressif/frameworks/esp-idf-v4.4/components/lwip/include/apps/sntp -IC:/Espressif/frameworks/esp-idf-v4.4/components/lwip/lwip/src/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/lwip/port/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/lwip/port/esp32/include/arch -IC:/Espressif/frameworks/esp-idf-v4.4/components/soc/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/soc/esp32/. -IC:/Espressif/frameworks/esp-idf-v4.4/components/soc/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/hal/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/hal/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/hal/platform_port/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_rom/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_rom/include/esp32 -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_rom/esp32 -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_common/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_system/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_system/port/soc -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_system/port/public_compat -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/xtensa/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/xtensa/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/driver/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/driver/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_pm/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_ringbuf/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/efuse/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/efuse/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/vfs/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_wifi/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_event/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_eth/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/tcpip_adapter/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_phy/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_phy/esp32/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_ipc/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/app_trace/include -IC:/Espressif/frameworks/esp-idf-v4.4/components/esp_timer/include -mlongcalls -Wno-frame-address -ffunction-sections -fdata-sections -Wall -Werror=all -Wno-error=unused-function -Wno-error=unused-variable -Wno-error=deprecated-declarations -Wextra -Wno-unused-parameter -Wno-sign-compare -ggdb -Og -fmacro-prefix-map=C:/BLR/platform/edge-rtos-app-esp32/esp32_common/esp-idf/examples/protocols/http2_request=. -fmacro-prefix-map=C:/Espressif/frameworks/esp-idf-v4.4=IDF -fstrict-volatile-bitfields -Wno-error=unused-but-set-variable -fno-jump-tables -fno-tree-switch-conversion -std=gnu99 -Wno-old-style-declaration -D_GNU_SOURCE -DIDF_VER=\"v4.4\" -DESP_PLATFORM -D_POSIX_READER_WRITER_LOCKS -MD -MT esp-idf/esp_netif/CMakeFiles/__idf_esp_netif.dir/lwip/esp_netif_lwip_defaults.c.obj -MF esp-idf\esp_netif\CMakeFiles\__idf_esp_netif.dir\lwip\esp_netif_lwip_defaults.c.obj.d -o esp-idf/esp_netif/CMakeFiles/__idf_esp_netif.dir/lwip/esp_netif_lwip_defaults.c.obj -c C:/Espressif/frameworks/esp-idf-v4.4/components/esp_netif/lwip/esp_netif_lwip_defaults.c
In file included from C:/Espressif/frameworks/esp-idf-v4.4/components/tcpip_adapter/include/tcpip_adapter_types.h:19,
                 from C:/Espressif/frameworks/esp-idf-v4.4/components/tcpip_adapter/include/tcpip_adapter.h:24,
                 from C:/Espressif/frameworks/esp-idf-v4.4/components/esp_netif/include/esp_netif.h:35,
                 from C:/Espressif/frameworks/esp-idf-v4.4/components/esp_netif/lwip/esp_netif_lwip_defaults.c:15:
C:/Espressif/frameworks/esp-idf-v4.4/components/lwip/include/apps/dhcpserver/dhcpserver.h:45:2: error: unknown type name 'ip4_addr_t'
  ip4_addr_t start_ip;
  ^~~~~~~~~~
C:/Espressif/frameworks/esp-idf-v4.4/components/lwip/include/apps/dhcpserver/dhcpserver.h:46:2: error: unknown type name 'ip4_addr_t'
  ip4_addr_t end_ip;
  ^~~~~~~~~~
C:/Espressif/frameworks/esp-idf-v4.4/components/lwip/include/apps/dhcpserver/dhcpserver.h:62:2: error: unknown type name 'ip4_addr_t'
  ip4_addr_t ip;
  ^~~~~~~~~~
C:/Espressif/frameworks/esp-idf-v4.4/components/lwip/include/apps/dhcpserver/dhcpserver.h:89:39: error: unknown type name 'ip4_addr_t'; did you mean 'ip_addr_t'?
 void dhcps_start(struct netif *netif, ip4_addr_t ip);
                                       ^~~~~~~~~~

More Information.

No response

[sgryphon]

I am not sure if it is relevant for your scenario, but I recently put up a pull request to update the protocol examples to work with all/any network configuration. The branch is here: #13250

The update examples work out of the box (no config or code changes) with all network types: IPv4-only, IPv6-only, and dual stack. (You do need to provide config for things like your WiFi password)

Note that this is not the same as turning off IPv4 -- IPv4 is still turned on, just not used. The updated example works in an IPv6-only network, if that is your objective. See the example outputs for IPv6-only network. If you have DNS64/NAT64 available, then it can even connect from an IPv6-only network to an IPv4-only server.

However, IPv4 is still actually on.

If you know IPv4 is not necessary, e.g. if you are developing a Matter device where only IPv6 is required, and want to reduce memory size and development/testing effort, then you could also turn off IPv4 completely.

[sgryphon]

I just tried turning off LWIP_IPV4 for the updated example, and it does break compilation (in the PPP component). The example still works on an IPv6-only network, it just needs IPv4 turned on (although not being used).

I will see if there is a quick fix for the example.

Fixed now... there was a small bug in the PPP component that broke compilation when LWIP_IPV4 was turned off. I have added a fix for that and the updated example now works when IPv4 is completely turned off.

I tested it in a dual stack environment, and the IPv6 code all ran, and it just never got an IPv4 address.

Note: In the general case you want to leave both IPv4 and IPv6 enabled (using whichever is available), as you may not know where it will be deployed. You only want to completely turn one off if you know it won't be necessary (e.g. Matter requires IPv6, so you know IPv6 will always be available) and want to save the size / complexity and turn it off.

If all you want to do is be able to access an IPv6-only need then the basic example is fine; leave IPv4 on and just don't use it on that network.

[espressif-abhikroy]

The option to disable IPv4 is not available for IDF release v4.4 and v5.0.
It's available from IDF release v5.1 onwards.
Closing the issue as it's duplicate of
espressif/esp-lwip#64