Catching Extra Semicolons After UVM Macros with UVMLint

A solution‑first guide to preventing the classic dangling else error caused by UVM reporting macros.

UVMLint Rule: No Trailing Semicolon After UVM Reporting Macros

Define a lint rule that flags any UVM reporting macro invocation immediately followed by a semicolon.

Implementation detail: This rule should be parser‑aware. Avoid pure regex; require an AST/token stream so comments, strings, and macro line breaks are handled correctly.

Why This Rule Exists

Consider a simple user code as below:

 // Buggy code

if (debug_on)
  `uvm_info("DEBUG", "state info", UVM_LOW); //  semicolon here
else
  $display("Doing something else");

The UVM BCL defines `uvm_info as a complete begin...end block. Adding a semicolon after the macro turns into a null statement that terminates the if prematurely, leaving the else orphaned.

// UVM BCL (abridged)
`define uvm_info(ID,MSG,VERBOSITY) \
  begin \
    if (uvm_report_enabled(VERBOSITY,UVM_INFO,ID)) \
      uvm_report_info (ID, MSG, VERBOSITY, `uvm_file, `uvm_line); \
  end

So what's wrong? Let's expand the macro in-place.

 
// What the compiler effectively sees
if (debug_on)
  begin
    if (uvm_report_enabled(UVM_LOW,UVM_INFO,"DEBUG"))
      uvm_report_info("DEBUG","state info",UVM_LOW,`uvm_file,`uvm_line);
  end;  // null statement ends the 'if'
else
  $display("Doing something else"); // ← now orphaned

Fix: drop the trailing semicolon after the macro invocation.

if (debug_on)
  `uvm_info("DEBUG", "state info", UVM_LOW)
else
  $display("Doing something else");

Why Grep Isn’t Enough

Text search won’t reliably detect this class of errors:

• Multiline calls: macros can be split across lines; naive patterns miss them.
• Comments & strings: false positives from commented code or string literals.
• Macro families: the issue applies to multiple report macros, aliasing, and wrappers.
• Language context: only a parser can tell if a semicolon actually terminates an if branch.

Use a syntax‑aware linter (UVMLint or similar) that understands SystemVerilog tokens, comments, and macro expansion boundaries.

Takeaways

• UVM reporting macros expand into self‑contained begin...end blocks.
• Do not add a trailing semicolon when used under if/else.
• Enforce with a UVMLint rule; avoid brittle grep‑based checks.