Javascript jsc c++20 testing quirk fix

.github/workflows/linux.yml

@@ -329,6 +329,12 @@ jobs:
           CPPSTD: c++20
           GCC: 13
           os: ubuntu-22.04
+        - SWIGLANG: javascript
+          ENGINE: jsc
+          CPPSTD: c++20
+          VER: '4.1'
+          GCC: 13
+          os: ubuntu-22.04
         - SWIGLANG: javascript
           ENGINE: napi
           VER: '22'

Examples/test-suite/typemap_array_qualifiers.i

@@ -1,5 +1,10 @@
 %module typemap_array_qualifiers
 
+// Including this fragment ensures math.h is included before the '#define volatile' below,
+// without which gave peculiar partial specialization errors for javascript jsc and -std=c++20
+// - volatile is used in the template parameters of numeric_limits on Linux.
+%fragment("<math.h>");
+
 %define CLEAR_SWIGTYPE_TYPEMAPS
 %typemap(in)
    SWIGTYPE,