Add missing elements from newer versions of CodeView.

changelog/dmd.newpdb.dd

@@ -0,0 +1,19 @@
+Improved CodeView / PDB symbolic debug info on Windows
+
+The Windows CodeView / PDB debug information emitter (used with `-g` when producing MS-COFF object files) now emits additional modern records expected by Microsoft and LLVM debugging tools. These improvements are enabled by default, so debugging with Visual Studio, WinDbg and LLVM-based tools works better out of the box.
+
+The following are now generated:
+
+$(LIST
+    * `S_OBJNAME` and `S_COMPILE3` compiland records reporting the configured language and the real compiler version string,
+    * `S_ENVBLOCK` and `S_BUILDINFO` (`LF_BUILDINFO`) records describing the build environment,
+    * `S_FRAMEPROC` records describing each function's stack frame,
+    * `LF_UDT_SRC_LINE` records recording the source file and line where each user-defined type (struct, class, enum) is defined, so debuggers can jump to a type's definition,
+    * blake3 source-file checksums in the file-checksums subsection so debuggers can verify the source matches.
+)
+
+No action is required; simply compile with `-g` as before:
+
+```console
+dmd -g myapp.d
+```

compiler/src/dmd/backend/backconfig.d

@@ -17,7 +17,8 @@ import core.stdc.stdio;
 import dmd.backend.cdef;
 import dmd.backend.cc;
 import dmd.backend.code;
-import dmd.backend.global : ErrorCallbackBackend, error, errorCallbackBackend;
+import dmd.backend.global : ErrorCallbackBackend, error, errorCallbackBackend,
+    GetFileContentsCallback, getFileContentsCallback;
 import dmd.backend.go : go_flag, GlobalOptimizer;
 import dmd.backend.rtlsym : rtlsym_init;
 import dmd.backend.ty;
@@ -87,11 +88,13 @@ void out_config_init(
         bool generatedMain,     // a main entrypoint is generated
         bool dataimports,
         ref GlobalOptimizer go,
-        ErrorCallbackBackend errorCallback)
+        ErrorCallbackBackend errorCallback,
+        GetFileContentsCallback getFileContents)
 {
     //printf("out_config_init()\n");
 
     errorCallbackBackend = errorCallback;
+    getFileContentsCallback = getFileContents;
     auto cfg = &config;
 
     cfg._version = _version;