diff --git a/src/linter/cache.go b/src/linter/cache.go
index b893fbd1..b18c7a5a 100644
--- a/src/linter/cache.go
+++ b/src/linter/cache.go
@@ -17,41 +17,42 @@ import (
 //
 // Version log:
 //
-//	27 - added Static field to meta.FuncInfo
-//	28 - array type parsed as mixed[]
-//	29 - updated type inference for ClassConstFetch
-//	30 - resolve ClassConstFetch to a wrapped type string
-//	31 - fixed plus operator type inference for arrays
-//	32 - replaced Static:bool with Flags:uint8 in meta.FuncInfo
-//	33 - support parsing of array<k,v> and list<type>
-//	34 - support parsing of ?ClassName as "ClassName|null"
-//	35 - added Flags:uint8 to meta.ClassInfo
-//	36 - added FuncAbstract bit to FuncFlags
-//	     added FuncFinal bit to FuncFlags
-//	     added ClassFinal bit to ClassFlags
-//	     FuncInfo now stores original function name
-//	     ClassInfo now stores original class name
-//	37 - added ClassShape bit to ClassFlags
-//	     changed meta.scopeVar bool fields representation
-//	38 - replaced TypesMap.immutable:bool with flags:uint8.
-//	     added mapPrecise flag to mark precise type maps.
-//	39 - added new field Value in ConstantInfo
-//	40 - changed string const value storage (no quotes)
-//	41 - const-folding affected const definition values
-//	42 - bool-typed consts are now stored in meta info
-//	43 - define'd const values stored in cache
-//	44 - rename ConstantInfo => ConstInfo
-//	45 - added Mixins field to meta.ClassInfo
-//	46 - changed the way of inferring the return type of functions and methods
-//	47 - forced cache version invalidation due to the #921
-//	48 - renamed meta.TypesMap to types.Map; this affects gob encoding
-//	49 - for shape, names are now generated using the keys that make up this shape
-//	50 - added Flags field for meta.PropertyInfo
-//	51 - added anonymous classes
-//	52 - renamed all PhpDoc and Phpdoc with PHPDoc
-//	53 - added DeprecationInfo for functions and methods and support for some attributes
-//	54 - forced cache version invalidation due to the #1165
-const cacheVersion = 54
+//		27 - added Static field to meta.FuncInfo
+//		28 - array type parsed as mixed[]
+//		29 - updated type inference for ClassConstFetch
+//		30 - resolve ClassConstFetch to a wrapped type string
+//		31 - fixed plus operator type inference for arrays
+//		32 - replaced Static:bool with Flags:uint8 in meta.FuncInfo
+//		33 - support parsing of array<k,v> and list<type>
+//		34 - support parsing of ?ClassName as "ClassName|null"
+//		35 - added Flags:uint8 to meta.ClassInfo
+//		36 - added FuncAbstract bit to FuncFlags
+//		     added FuncFinal bit to FuncFlags
+//		     added ClassFinal bit to ClassFlags
+//		     FuncInfo now stores original function name
+//		     ClassInfo now stores original class name
+//		37 - added ClassShape bit to ClassFlags
+//		     changed meta.scopeVar bool fields representation
+//		38 - replaced TypesMap.immutable:bool with flags:uint8.
+//		     added mapPrecise flag to mark precise type maps.
+//		39 - added new field Value in ConstantInfo
+//		40 - changed string const value storage (no quotes)
+//		41 - const-folding affected const definition values
+//		42 - bool-typed consts are now stored in meta info
+//		43 - define'd const values stored in cache
+//		44 - rename ConstantInfo => ConstInfo
+//		45 - added Mixins field to meta.ClassInfo
+//		46 - changed the way of inferring the return type of functions and methods
+//		47 - forced cache version invalidation due to the #921
+//		48 - renamed meta.TypesMap to types.Map; this affects gob encoding
+//		49 - for shape, names are now generated using the keys that make up this shape
+//		50 - added Flags field for meta.PropertyInfo
+//		51 - added anonymous classes
+//		52 - renamed all PhpDoc and Phpdoc with PHPDoc
+//		53 - added DeprecationInfo for functions and methods and support for some attributes
+//		54 - forced cache version invalidation due to the #1165
+//	 55 - updated go version 1.16 -> 1.21
+const cacheVersion = 55
 
 var (
 	errWrongVersion = errors.New("Wrong cache version")
diff --git a/src/linter/cache_test.go b/src/linter/cache_test.go
index de0386b0..8281dc48 100644
--- a/src/linter/cache_test.go
+++ b/src/linter/cache_test.go
@@ -148,8 +148,8 @@ main();
 		// 1. Check cache contents length.
 		//
 		// If cache encoding changes, there is a very high chance that
-		// encoded data length will change as well.
-		wantLen := 5953
+		// encoded data lengh will change as well.
+		wantLen := 5952
 		haveLen := buf.Len()
 		if haveLen != wantLen {
 			t.Errorf("cache len mismatch:\nhave: %d\nwant: %d", haveLen, wantLen)
@@ -158,7 +158,7 @@ main();
 		// 2. Check cache "strings" hash.
 		//
 		// It catches new fields in cached types, field renames and encoding of additional named attributes.
-		wantStrings := "df69cfe531807fe5e317e5f894ac1ad2a68020edf03a053a30b25c70488b741b6d992d37e7a76ac4b8a760756631ee9ae309ba57e29253ffae896c3492b90939"
+		wantStrings := "690e77c94ecdd7878de0bf6f6881d786cf1fafa4588f7905f54d700646c4952aad359008ae2dcddb1c7f29163ecee62355d525672090ac30257bc414f690006f"
 		haveStrings := collectCacheStrings(buf.String())
 		if haveStrings != wantStrings {
 			t.Errorf("cache strings mismatch:\nhave: %q\nwant: %q", haveStrings, wantStrings)