Fix undefined behaviors caught by ubsan

This fixes a couple of integer overflows in parsing as well as removes
the construction of a null reference that never got dereferenced.
This also initializes the bool members in TCall
Finally, this adds a UBSAN run alongside ASAN and TSAN in CI.

glslang/MachineIndependent/preprocessor/Pp.cpp

@@ -374,7 +374,7 @@ namespace {
     int op_div(int a, int b) { return a == INT_MIN && b == -1 ? 0 : a / b; }
     int op_mod(int a, int b) { return a == INT_MIN && b == -1 ? 0 : a % b; }
     int op_pos(int a) { return a; }
-    int op_neg(int a) { return -a; }
+    int op_neg(int a) { return a == INT_MIN ? INT_MIN : -a; }
     int op_cmpl(int a) { return ~a; }
     int op_not(int a) { return !a; }