Compiler bug: "expected an instance declaration"

[jnfoster]

The following program

//architecture
parser Parser();
parser MyParser(Parser p);
package Package(MyParser p1, MyParser p2);

//program
parser Parser1(Parser p) {
  state start {
   p.apply();
   transition accept;
  }
}

parser Parser2(Parser p) {
  state start {
   p.apply();
   transition accept;
  }
}

Parser1() p1;
Parser2() p2;

Package(p1,p2) main;

crashes with a compiler bug:

terminate called after throwing an instance of 'Util::CompilerBug'
  what():  COMPILER BUG: ../midend/inlining.cpp:255
bug2.p4(6): <Parameter>(33) <Type_Name>(32):Parser p expected an instance declaration
parser Parser1(Parser p) {
               ^^^^^^^^

[mihaibudiu]

I will change the spec to forbid parsers, controls and packages to be passed as arguments (they can only be passed as constructor arguments). So this program will fail with an error. This should also take care of the problem of the architecture passing parsers as arguments to parsers.

I have checked-in two examples that test passing parsers as arguments, testdata/p4_16_*/parser-arg.p4. The examples and fixes will be part of the next pull request.

[jnfoster]

Should global variables whose type is a parser, control, or package also be forbidden?

[mihaibudiu]

main is such a global instance.

[jnfoster]

Good point :-)