Change .vlt config files to be read before .v files (#5185).

Changes

@@ -17,6 +17,7 @@ Verilator 5.029 devel
 
 **Minor:**
 
+* Change .vlt config files to be read before .v files (#5185). [David Moberg]
 * Support IEEE-compliant intra-assign delays (#3711) (#5441). [Krzysztof Bieganski, Antmicro Ltd.]
 * Support unconstrained randomization for unions (#5395) (#5396). [Yilou Wang]
 * Support appending to queue via `[]` (#5421). [Krzysztof Bieganski, Antmicro Ltd.]

docs/guide/exe_verilator.rst

@@ -1909,8 +1909,12 @@ Configuration Files
 
 In addition to the command line, warnings and other features for the
 :command:`verilator` command may be controlled with configuration files,
-typically named with the .vlt extension (what makes it a configuration file
-is the :option:`\`verilator_config` directive). An example:
+typically named with the `.vlt` extension (what makes it a configuration
+file is the :option:`\`verilator_config` directive).  These files, when
+named `.vlt`, are read before source code files; if this behavior is
+undesired, name the config file with a `.v` suffix.
+
+An example:
 
 .. code-block:: sv
 

src/V3Global.cpp

@@ -58,6 +58,13 @@ void V3Global::readFiles() {
 
     V3Parse parser{v3Global.rootp(), &filter, &parseSyms};
 
+    // Read .vlt files
+    const V3StringSet& vltFiles = v3Global.opt.vltFiles();
+    for (const string& filename : vltFiles) {
+        parser.parseFile(new FileLine{FileLine::commandLineFilename()}, filename, false,
+                         "Cannot find file containing .vlt file: ");
+    }
+
     // Parse the std package
     if (v3Global.opt.std()) {
         parser.parseFile(new FileLine{V3Options::getStdPackagePath()},

src/V3Options.cpp

@@ -395,6 +395,7 @@ void V3Options::addVFile(const string& filename) {
     // in a specific order and multiple of them.
     m_vFiles.push_back(filename);
 }
+void V3Options::addVltFile(const string& filename) { m_vltFiles.insert(filename); }
 void V3Options::addForceInc(const string& filename) { m_forceIncs.push_back(filename); }
 
 void V3Options::addLineArg(const string& arg) { m_impp->m_lineArgs.push_back(arg); }
@@ -1772,6 +1773,8 @@ void V3Options::parseOptsList(FileLine* fl, const string& optdir, int argc,
                        || suffixed(filename, ".o")  //
                        || suffixed(filename, ".so")) {
                 V3Options::addLdLibs(filename);
+            } else if (suffixed(filename, ".vlt")) {
+                V3Options::addVltFile(filename);
             } else {
                 V3Options::addVFile(filename);
             }

src/V3Options.h

@@ -210,6 +210,7 @@ private:
     V3StringSet m_clockers;     // argument: Verilog -clk signals
     V3StringSet m_noClockers;   // argument: Verilog -noclk signals
     V3StringList m_vFiles;      // argument: Verilog files to read
+    V3StringSet m_vltFiles;     // argument: Verilator config files to read
     V3StringList m_forceIncs;   // argument: -FI
     DebugLevelMap m_debugLevel; // argument: --debugi-<srcfile/tag> <level>
     DebugLevelMap m_dumpLevel;  // argument: --dumpi-<srcfile/tag> <level>
@@ -444,6 +445,7 @@ public:
     void addClocker(const string& signame);
     void addNoClocker(const string& signame);
     void addVFile(const string& filename);
+    void addVltFile(const string& filename);
     void addForceInc(const string& filename);
     bool available() const VL_MT_SAFE { return m_available; }
     void ccSet();
@@ -638,6 +640,7 @@ public:
     const V3StringList& makeFlags() const { return m_makeFlags; }
     const V3StringSet& libraryFiles() const { return m_libraryFiles; }
     const V3StringList& vFiles() const { return m_vFiles; }
+    const V3StringSet& vltFiles() const { return m_vltFiles; }
     const V3StringList& forceIncs() const { return m_forceIncs; }
 
     bool hasParameter(const string& name);

test_regress/t/t_vlt_match_error_1.out

@@ -1,7 +1,3 @@
-%Error-PKGNODECL: t/t_vlt_match_error.v:17:12: Package/class 'hi' not found, and needs to be predeclared (IEEE 1800-2023 26.3)
-   17 |     import hi::*;
-      |            ^~
-                  ... For error description see https://verilator.org/warn/PKGNODECL?v=latest
 %Error: t/t_vlt_match_error.v:17:12: Importing from missing package 'hi'
    17 |     import hi::*;
       |            ^~