[asan] Remove "Stack partial redzone" from report

[vitalybuka]

Summary

This value is never used.

[kcc]

LGTM

[vitalybuka]

Rebase

lib/asan/asan_descriptions.h

switch (byte) {
       case kAsanHeapRightRedzoneMagic:
       case kAsanArrayCookieMagic:
         return Red();
       case kAsanHeapFreeMagic:
         return Magenta();
       case kAsanStackLeftRedzoneMagic:
       case kAsanStackMidRedzoneMagic:
       case kAsanStackRightRedzoneMagic:
-      case kAsanStackPartialRedzoneMagic:
         return Red();
       case kAsanStackAfterReturnMagic:
         return Magenta();
       case kAsanInitializationOrderMagic:
         return Cyan();
       case kAsanUserPoisonedMemoryMagic:
       case kAsanContiguousContainerOOBMagic:
       case kAsanAllocaLeftMagic:

lib/asan/asan_internal.h

 extern void (*death_callback)(void);
 // These magic values are written to shadow for better error reporting.
 const int kAsanHeapLeftRedzoneMagic = 0xfa;
 const int kAsanHeapRightRedzoneMagic = 0xfb;
 const int kAsanHeapFreeMagic = 0xfd;
 const int kAsanStackLeftRedzoneMagic = 0xf1;
 const int kAsanStackMidRedzoneMagic = 0xf2;
 const int kAsanStackRightRedzoneMagic = 0xf3;
-const int kAsanStackPartialRedzoneMagic = 0xf4;
 const int kAsanStackAfterReturnMagic = 0xf5;
 const int kAsanInitializationOrderMagic = 0xf6;
 const int kAsanUserPoisonedMemoryMagic = 0xf7;
 const int kAsanContiguousContainerOOBMagic = 0xfc;
 const int kAsanStackUseAfterScopeMagic = 0xf8;
 const int kAsanGlobalRedzoneMagic = 0xf9;
 const int kAsanInternalHeapMagic = 0xfe;
 const int kAsanArrayCookieMagic = 0xac;

lib/asan/asan_report.cc

PrintShadowByte(str, "  Heap right redzone:      ",
                   kAsanHeapRightRedzoneMagic);
   PrintShadowByte(str, "  Freed heap region:       ", kAsanHeapFreeMagic);
   PrintShadowByte(str, "  Stack left redzone:      ",
                   kAsanStackLeftRedzoneMagic);
   PrintShadowByte(str, "  Stack mid redzone:       ",
                   kAsanStackMidRedzoneMagic);
   PrintShadowByte(str, "  Stack right redzone:     ",
                   kAsanStackRightRedzoneMagic);
-  PrintShadowByte(str, "  Stack partial redzone:   ",
-                  kAsanStackPartialRedzoneMagic);
   PrintShadowByte(str, "  Stack after return:      ",
                   kAsanStackAfterReturnMagic);
   PrintShadowByte(str, "  Stack use after scope:   ",
                   kAsanStackUseAfterScopeMagic);
   PrintShadowByte(str, "  Global redzone:          ", kAsanGlobalRedzoneMagic);
   PrintShadowByte(str, "  Global init order:       ",
                   kAsanInitializationOrderMagic);
   PrintShadowByte(str, "  Poisoned by user:        ",
switch (shadow_val) {
         far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
         break;
       case kAsanInitializationOrderMagic:
         bug_descr = "initialization-order-fiasco";
         bug_type_score = 1;
         break;
       case kAsanStackMidRedzoneMagic:
       case kAsanStackRightRedzoneMagic:
-      case kAsanStackPartialRedzoneMagic:
         bug_descr = "stack-buffer-overflow";
         bug_type_score = 25;
         far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
         break;
       case kAsanStackAfterReturnMagic:
         bug_descr = "stack-use-after-return";
         bug_type_score = 30;
         if (!is_write) read_after_free_bonus = 18;