Fix module stats output to not crash on printing sans-class modules.

Fixes #478

.vscode/launch.json

@@ -4,6 +4,25 @@
 	// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
 	"version": "0.2.0",
 	"configurations": [
+		{
+			"name": "(gdb) Launch",
+			"type": "cppdbg",
+			"request": "launch",
+			"program": "${workspaceFolder}/.build/gcc-15/debug/cxxstd-11-iso/threading-multi/b2",
+			"args": ["-d9"],
+			"stopAtEntry": false,
+			"cwd": "${workspaceFolder}/example/hello",
+			"environment": [],
+			"externalConsole": false,
+			"MIMode": "gdb",
+			"setupCommands": [
+				{
+					"description": "Enable pretty-printing for gdb",
+					"text": "-enable-pretty-printing",
+					"ignoreFailures": true
+				}
+			]
+		},
 		{
 			"name": "(gdb) Pipe Launch",
 			"type": "cppdbg",
@@ -17,10 +36,7 @@
 			"pipeTransport": {
 				"debuggerPath": "/usr/local/bin/gdb",
 				"pipeProgram": "/usr/bin/ssh",
-				"pipeArgs": [
+				"pipeArgs": ["-v", "root@192.168.13.163"],
-					"-v",
-					"root@192.168.13.163"
-				],
 				"pipeCwd": ""
 			},
 			"MIMode": "gdb",
@@ -40,9 +56,7 @@
 			"type": "cppdbg",
 			"request": "launch",
 			"program": "${workspaceFolder}\\.build\\gcc-10\\debug\\cxxstd-11-iso\\b2.exe",
-			"args": [
+			"args": ["-v"],
-				"-v"
-			],
 			"stopAtEntry": false,
 			"cwd": "${workspaceFolder}",
 			"environment": [],
@@ -67,9 +81,7 @@
 			"type": "cppvsdbg",
 			"request": "launch",
 			"program": "${workspaceFolder}\\.build\\msvc-14.3\\debug\\cxxstd-11-iso\\threading-multi\\b2.exe",
-			"args": [
+			"args": ["-ftest.jam"],
-				"-ftest.jam"
-			],
 			"stopAtEntry": false,
 			"cwd": "${workspaceFolder}\\test",
 			"environment": [
@@ -84,11 +96,7 @@
 			"type": "cppvsdbg",
 			"request": "launch",
 			"program": "${workspaceFolder}\\.build\\msvc-14.3\\debug\\cxxstd-11-iso\\threading-multi\\b2.exe",
-			"args": [
+			"args": ["--debug", "--build-system=test/test", "-j1"],
-				"--debug",
-				"--build-system=test/test",
-				"-j1"
-			],
 			"stopAtEntry": false,
 			"cwd": "${workspaceFolder}\\test",
 			"environment": []
@@ -98,9 +106,7 @@
 			"type": "cppdbg",
 			"request": "launch",
 			"program": "${workspaceFolder}/.build/gcc-14/debug/cxxstd-11-iso/threading-multi/b2",
-			"args": [
+			"args": ["-h"],
-				"-h"
-			],
 			"stopAtEntry": false,
 			"cwd": "${workspaceFolder}/example/hello",
 			"environment": [],
@@ -119,10 +125,7 @@
 			"type": "cppdbg",
 			"request": "launch",
 			"program": "${workspaceFolder}/.build/gcc-14/debug/address-sanitizer-on/cxxstd-11-iso/threading-multi/b2",
-			"args": [
+			"args": ["-n", "-a"],
-				"-n",
-				"-a"
-			],
 			"stopAtEntry": false,
 			"cwd": "${workspaceFolder}",
 			"environment": [],
@@ -193,12 +196,10 @@
 			"name": "(rr) Launch",
 			"type": "cppdbg",
 			"request": "launch",
-			"program": "${workspaceFolder}/.build/gcc-14/debug/cxxstd-11-iso/b2",
+			"program": "${workspaceFolder}/.build/gcc-15/debug/cxxstd-11-iso/threading-multi/b2",
-			"args": [
+			"args": ["-d9"],
-				"--grep"
-			],
 			"stopAtEntry": false,
-			"cwd": "${workspaceFolder}",
+			"cwd": "${workspaceFolder}/example/hello",
 			"environment": [],
 			"externalConsole": true,
 			"MIMode": "gdb",
@@ -216,4 +217,4 @@
 			]
 		}
 	]
-}
+}

doc/src/history.adoc

@@ -39,6 +39,8 @@
   -- _Uilian Ries_
 * Fix resolution of subprojects of rooted projects.
   -- _Dmitry Arkhipov_
+* Fix crash when using `-d9` to output module debug stats.
+  -- _René Ferdinand Rivera Morell_
 
 == Version 5.3.3
 

src/engine/modules.cpp

@@ -205,7 +205,7 @@ static void stat_module( void * xmodule, void * data )
     if ( is_debug_mem() || is_debug_profile() )
     {
         struct hash * class_info = (struct hash *)data;
-        if ( m->class_module )
+        if ( m->class_module && m->class_module->name )
         {
             int found;
             struct module_stats * ms = (struct module_stats *)hash_insert( class_info, m->class_module->name, &found );

src/engine/modules.h

@@ -22,16 +22,16 @@ typedef module_t * module_ptr;
 
 struct module_t
 {
-    OBJECT * name;
+    OBJECT * name = nullptr;
-    struct hash * rules;
+    struct hash * rules = nullptr;
-    struct hash * variables;
+    struct hash * variables = nullptr;
-    struct hash * variable_indices;
+    struct hash * variable_indices = nullptr;
-    int num_fixed_variables;
+    int num_fixed_variables = 0;
-    LIST * * fixed_variables;
+    LIST * * fixed_variables = nullptr;
-    struct hash * imported_modules;
+    struct hash * imported_modules = nullptr;
-    module_t * class_module;
+    module_t * class_module = nullptr;
-    struct hash * native_rules;
+    struct hash * native_rules = nullptr;
-    int user_module;
+    int user_module = 0;
 };
 
 module_t * bindmodule( OBJECT * name );