[BUG] E0_AUTO_FAN_PIN sanity check for FAN0_PIN is not triggred

[ellensp]

Did you test the latest bugfix-2.1.x code?

Yes, and the problem still exists.

Bug Description

Take stock Configs, set #define E0_AUTO_FAN_PIN FAN0_PIN
Watch as Marlin compiles without any issues
despite having the following in sanity check.

    #if PIN_EXISTS(E0_AUTO_FAN) && E0_AUTO_FAN_PIN == FAN0_PIN
      #error "You cannot set E0_AUTO_FAN_PIN equal to FAN0_PIN."

Bug Timeline

Since #25568

Expected behavior

This should trigger the error in sanity check "You cannot set E0_AUTO_FAN_PIN equal to FAN0_PIN."

Actual behavior

no error

Steps to Reproduce

1. set #define E0_AUTO_FAN_PIN FAN0_PIN
2. compile
3. note it compiles without error

Version of Marlin Firmware

Bugfix-2.1.x

[ellensp]

In Marlin/src/inc/SanityCheck.h is the following code

#if HAS_AUTO_FAN
  #if HAS_FAN0
    #if PIN_EXISTS(E0_AUTO_FAN) && E0_AUTO_FAN_PIN == FAN0_PIN
      #error "You cannot set E0_AUTO_FAN_PIN equal to FAN0_PIN."
    #elif PIN_EXISTS(E1_AUTO_FAN) && E1_AUTO_FAN_PIN == FAN0_PIN
      #error "You cannot set E1_AUTO_FAN_PIN equal to FAN0_PIN."
    #elif PIN_EXISTS(E2_AUTO_FAN) && E2_AUTO_FAN_PIN == FAN0_PIN
      #error "You cannot set E2_AUTO_FAN_PIN equal to FAN0_PIN."
    #elif PIN_EXISTS(E3_AUTO_FAN) &&  E3_AUTO_FAN_PIN == FAN0_PIN
      #error "You cannot set E3_AUTO_FAN_PIN equal to FAN0_PIN."
    #endif
  #endif
#endif

But HAS_FAN0 is not set, so this block is ignored.

In Marlin/src/inc/Conditionals_post.h has this code

#define _IS_E_AUTO(N,F) (PIN_EXISTS(E##N##_AUTO_FAN) && E##N##_AUTO_FAN_PIN == FAN##F##_PIN)
#define _HAS_FAN(F) (F < MAX_FANS && PIN_EXISTS(FAN##F) \
                     && !(HAS_CONTROLLER_FAN && CONTROLLER_FAN_PIN == FAN##F##_PIN) \
                     && !_IS_E_AUTO(0,F) && !_IS_E_AUTO(1,F) \
                     && !_IS_E_AUTO(2,F) && !_IS_E_AUTO(3,F) \
                     && !_IS_E_AUTO(4,F) && !_IS_E_AUTO(5,F) \
                     && !_IS_E_AUTO(6,F) && !_IS_E_AUTO(7,F))

#if _HAS_FAN(0)
  #define HAS_FAN0 1
#endif

The test explicitly checks for E0_AUTO_FAN == FAN0_PIN and tells marlin that HAS_FAN0 is false, disabling the sanity check.

[ellensp]

proposal, treat FAN0 as special, only check it has been defined. as it was originally

diff --git a/Marlin/src/inc/Conditionals_post.h b/Marlin/src/inc/Conditionals_post.h
index 04e96177b5..d946904e75 100644
--- a/Marlin/src/inc/Conditionals_post.h
+++ b/Marlin/src/inc/Conditionals_post.h
@@ -2657,7 +2657,7 @@
                      && !_IS_E_AUTO(4,F) && !_IS_E_AUTO(5,F) \
                      && !_IS_E_AUTO(6,F) && !_IS_E_AUTO(7,F))
 
-#if _HAS_FAN(0)
+#if PIN_EXISTS(FAN0)
   #define HAS_FAN0 1
 #endif
 #if _HAS_FAN(1)

[thisiskeithb]

proposal, treat FAN0 as special, only check it has been defined. as it was originally

Can confirm that the sanity check now fails when it should.

[ellensp]

PR created, closing.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.