[BUG] Build failure with DNS cache disabled

[jackwilsdon]

Describe the bug

#define ipconfigUSE_DNS_CACHE 0

Removes the pcName field from ParseSet_t:

FreeRTOS-Plus-TCP/source/include/FreeRTOS_DNS_Globals.h

Lines 192 to 196 in 57c1967

	#if ( ipconfigUSE_DNS_CACHE == 1 ) || ( ipconfigDNS_USE_CALLBACKS == 1 ) || ( ipconfigUSE_MDNS == 1 )
	BaseType_t xDoStore; /**< Becomes true when a DNS reply was requested by this device,
	* i.e. it has a matching request ID. */
	char pcName[ ipconfigDNS_CACHE_NAME_LENGTH ]; /**< A copy of the name that is mentioned in the questions. */
	#endif

But pcName is still used by DNS_ReadNameField:

FreeRTOS-Plus-TCP/source/FreeRTOS_DNS_Parser.c

Line 104 in 57c1967

pxSet->pcName[ uxNameLen ] = '.';

Target

• Development board: Raspberry Pi Pico
• Instruction Set Architecture: ARMv6-M
• IDE and version: N/A
• Toolchain and version: arm-none-eabi-gcc (15:13.2.rel1-2) 13.2.1 20231009

Host

• Host OS: Linux
• Version: Debian GNU/Linux trixie/sid

To Reproduce

• Set ipconfigUSE_DNS_CACHE to 0
• Note that FreeRTOS-Plus-TCP no longer compiles

Expected behavior
FreeRTOS-Plus-TCP should compile with the DNS cache disabled.

Additional context
I'm on version 4.2.2 but can reproduce on main too.

[archigup]

Hi thanks for bringing this up! We're looking into this.

[AniruddhaKanhere]

Hello @jackwilsdon,

Thank you for bringing this to our attention. You are absolutely correct. This is a bug in how the #ifs are used.

The issue here is that the function DNS_ReadNameField only gets invoked when the DNS cache is enabled. But, it gets compiled with or without DNS cache being enabled. We should add a #if ( ipconfigUSE_DNS_CACHE == 1 ) around the function declaration and definition. We will raise a PR to fix it shortly.

Thanks again,
Aniruddha

[AniruddhaKanhere]

Hello @jackwilsdon, the above PR #1201 is merged in. Can you verify that the fix works for you?

Thanks,
Aniruddha

[ActoryOu]

We're closing this issue as the patch has been successfully merged. If you encounter any further related issues, please don't hesitate to reopen this thread.