diff --git a/.gitattributes b/.gitattributes
index d086c77db9..6233cef6b5 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -17805,6 +17805,7 @@ tests/webtbs/tw3768.pp svneol=native#text/plain
 tests/webtbs/tw3774.pp svneol=native#text/plain
 tests/webtbs/tw3777.pp svneol=native#text/plain
 tests/webtbs/tw3778.pp svneol=native#text/plain
+tests/webtbs/tw37796.pp svneol=native#text/pascal
 tests/webtbs/tw3780.pp svneol=native#text/plain
 tests/webtbs/tw37806.pp svneol=native#text/pascal
 tests/webtbs/tw3782.pp svneol=native#text/plain
diff --git a/compiler/htypechk.pas b/compiler/htypechk.pas
index ebe33104bc..078cbb31d2 100644
--- a/compiler/htypechk.pas
+++ b/compiler/htypechk.pas
@@ -1781,6 +1781,7 @@ implementation
                  mayberesettypeconvs;
                  exit;
                end;
+             arrayconstructorn,
              setconstn,
              stringconstn,
              guidconstn :
@@ -2082,6 +2083,7 @@ implementation
                  (tstringdef(def_to).encoding=tstringdef(p.resultdef).encoding) then
                 eq:=te_equal
             end;
+          formaldef,
           setdef :
             begin
               { set can also be a not yet converted array constructor }
diff --git a/compiler/ncal.pas b/compiler/ncal.pas
index f10f8dd30e..46950ef104 100644
--- a/compiler/ncal.pas
+++ b/compiler/ncal.pas
@@ -1205,6 +1205,13 @@ implementation
                     (parasym.vardef.typ=setdef) then
                    inserttypeconv(left,parasym.vardef);
 
+                 { if an array constructor can be a set and it is passed to
+                   a formaldef, a set must be passed, see also issue #37796 }
+                 if (left.nodetype=arrayconstructorn) and
+                    (parasym.vardef.typ=formaldef) and
+                    (arrayconstructor_can_be_set(left)) then
+                   left:=arrayconstructor_to_set(left,false);
+
                  { set some settings needed for arrayconstructor }
                  if is_array_constructor(left.resultdef) then
                   begin
diff --git a/tests/webtbs/tw37796.pp b/tests/webtbs/tw37796.pp
new file mode 100644
index 0000000000..98aa6f93a9
--- /dev/null
+++ b/tests/webtbs/tw37796.pp
@@ -0,0 +1,38 @@
+program tformal;
+{$mode objfpc}
+
+uses
+  sysutils;
+
+type
+  TFontStyle = (
+    fsItalic,
+    fsBold,
+    fsUnderlined,
+    fsStrikeOut
+  );
+  TFontStyles = set of TFontStyle;
+
+var aFS: TFontStyles;
+
+procedure Any(const Anything);
+begin
+  aFS:=aFS+TFontStyles(Anything);
+  Writeln(IntToHex(PLongInt(@Anything)^, 8));
+end;
+
+procedure DoIt;
+begin
+  Any([fsItalic, fsBold]); //unit1.pas(31,25) Error: Variable identifier expected
+  if aFS<>[fsItalic, fsBold] then
+    halt(1);
+  Any(Cardinal([fsItalic, fsBold])); //ok
+end;
+
+begin
+  aFS:=[];
+  writeln(Cardinal(aFS));
+  DoIt;
+  writeln(Cardinal(aFS));
+  writeln('ok');
+end.