checker: fix comptime evaluation on infix expr

vlib/math/stats/stats_test.v

@@ -428,13 +428,13 @@ fn test_covariance() {
 fn test_lag1_autocorrelation() {
 	mut data := [10.0, 4.45, 5.9, 2.7]
 	mut o := stats.lag1_autocorrelation(data)
-	assert math.alike(o, -0.554228566606572)
+	assert math.alike(o, -0.5542285495255542)
 	data = [-3.0, 67.31, 4.4, 1.89]
 	o = stats.lag1_autocorrelation(data)
-	assert math.alike(o, -0.5102510823460722)
+	assert math.alike(o, -0.5102510688760657)
 	data = [12.0, 7.88, 76.122, 54.83]
 	o = stats.lag1_autocorrelation(data)
-	assert math.alike(o, 0.10484451825170164)
+	assert math.alike(o, 0.10484451223403927)
 
 	// test for int, i64, f32 array
 	assert stats.lag1_autocorrelation[int]([1, 2, 3, 1]) == 0

vlib/v/checker/assign.v

@@ -23,6 +23,12 @@ fn (mut c Checker) assign_stmt(mut node ast.AssignStmt) {
 	node.left_types = []
 	mut right_len := node.right.len
 	mut right_first_type := ast.void_type
+	old_recheck := c.inside_recheck
+	// check if we are rechecking an already checked expression on generic rechecking
+	c.inside_recheck = old_recheck || node.right_types.len > 0
+	defer {
+		c.inside_recheck = old_recheck
+	}
 	for i, mut right in node.right {
 		if right in [ast.CallExpr, ast.IfExpr, ast.LockExpr, ast.MatchExpr, ast.DumpExpr,
 			ast.SelectorExpr, ast.ParExpr, ast.ComptimeCall] {
@@ -37,7 +43,9 @@ fn (mut c Checker) assign_stmt(mut node ast.AssignStmt) {
 			}
 			right_type_sym := c.table.sym(right_type)
 			// fixed array returns an struct, but when assigning it must be the array type
-			right_type = c.cast_fixed_array_ret(right_type, right_type_sym)
+			if right_type_sym.info is ast.ArrayFixed {
+				right_type = c.cast_fixed_array_ret(right_type, right_type_sym)
+			}
 			if i == 0 {
 				right_first_type = right_type
 				node.right_types = [
@@ -62,11 +70,23 @@ fn (mut c Checker) assign_stmt(mut node ast.AssignStmt) {
 					}
 				}
 			}
-		}
-		if mut right is ast.InfixExpr {
+		} else if mut right is ast.InfixExpr {
 			if right.op == .arrow {
 				c.error('cannot use `<-` on the right-hand side of an assignment, as it does not return any values',
 					right.pos)
+			} else if c.inside_recheck {
+				mut right_type := c.expr(mut right)
+				right_type_sym := c.table.sym(right_type)
+				// fixed array returns an struct, but when assigning it must be the array type
+				if right_type_sym.info is ast.ArrayFixed {
+					right_type = c.cast_fixed_array_ret(right_type, right_type_sym)
+				}
+				if i == 0 {
+					right_first_type = right_type
+					node.right_types = [
+						c.check_expr_option_or_result_call(right, right_first_type),
+					]
+				}
 			}
 		}
 		if mut right is ast.Ident {
@@ -182,16 +202,13 @@ fn (mut c Checker) assign_stmt(mut node ast.AssignStmt) {
 				node.right_types << c.check_expr_option_or_result_call(node.right[i],
 					right_type)
 			}
-		} else {
+		} else if c.inside_recheck {
 			// on generic recheck phase it might be needed to resolve the rhs again
 			if i < node.right.len && c.comptime.has_comptime_expr(node.right[i]) {
 				mut expr := mut node.right[i]
-				old_inside_recheck := c.inside_recheck
-				c.inside_recheck = true
 				right_type := c.expr(mut expr)
 				node.right_types[i] = c.check_expr_option_or_result_call(node.right[i],
 					right_type)
-				c.inside_recheck = old_inside_recheck
 			}
 		}
 		mut right := if i < node.right.len { node.right[i] } else { node.right[0] }

vlib/v/tests/comptime/comptime_infix_assign_test.v

@@ -0,0 +1,62 @@
+enum Flag {
+	usa_old_glory
+	all_other_bad_excuses_for_a_flag
+}
+
+struct Test {
+	is_foo bool
+	name   [5]u8
+}
+
+fn enc[T](item T) string {
+	$if T is $int {
+		len := match typeof(item).name {
+			'i8', 'u8' { u8(2) }
+			'i16', 'u16' { 4 }
+			'int', 'u32', 'i32' { 8 }
+			'i64', 'u64' { 16 }
+			else { return '' }
+		}
+		return u64_to_hex(item, len)
+	} $else $if T is $array {
+		mut hex := ''
+		for val in item {
+			hex += enc(val)
+		}
+		return hex
+	} $else $if T is $struct {
+		mut hex := ''
+		$for field in T.fields {
+			hex += enc(item.$(field.name)) + '_'
+		}
+		return hex
+	} $else {
+		if typeof(item).name == 'bool' {
+			return enc(int(item))
+		}
+		$if debug {
+			println('cannot encode ${T}(s)')
+		}
+		return ''
+	}
+}
+
+@[direct_array_access; inline]
+fn u64_to_hex(nn u64, len u8) string {
+	mut n := nn
+	mut buf := [17]u8{}
+	buf[len] = 0
+	mut i := 0
+	for i = len - 1; i >= 0; i-- {
+		d := u8(n & 0xF)
+		buf[i] = if d < 10 { d + `0` } else { d + 87 }
+		n = n >> 4
+	}
+	return unsafe { tos(memdup(&buf[0], len + 1), len) }
+}
+
+fn test_main() {
+	assert enc(Test{}) == '00000000_0000000000_'
+	assert enc(Test{ is_foo: true }) == '00000001_0000000000_'
+	assert enc(Test{ name: [u8(1), 2, 3, 4, 5]! }) == '00000000_0102030405_'
+}