Always provide /PDB option to linker if generating debug info.

radlink by default places the .PDB file in the working directory, even if /OUT says to place it elsewhere,
unlike link.exe, which places it next to the executable by default.

So, if compiling using -debug, we generate a PDB path even if -pdb-name wasn't used to override it.

src/build_settings.cpp

@@ -2066,10 +2066,6 @@ gb_internal bool init_build_paths(String init_filename) {
 			}
 		}
 
-		if (bc->pdb_filepath.len > 0) {
-			bc->build_paths[BuildPath_PDB]     = path_from_string(ha, bc->pdb_filepath);
-		}
-
 		if ((bc->command_kind & Command__does_build) && (!bc->ignore_microsoft_magic)) {
 			// NOTE(ic): It would be nice to extend this so that we could specify the Visual Studio version that we want instead of defaulting to the latest.
 			Find_Result find_result = find_visual_studio_and_windows_sdk();
@@ -2268,6 +2264,18 @@ gb_internal bool init_build_paths(String init_filename) {
 		bc->build_paths[BuildPath_Output] = output_path;
 	}
 
+	if (build_context.metrics.os == TargetOs_windows && build_context.ODIN_DEBUG) {
+		if (bc->pdb_filepath.len > 0) {
+			bc->build_paths[BuildPath_PDB] = path_from_string(ha, bc->pdb_filepath);
+		} else {
+			Path pdb_path;
+			pdb_path.basename = copy_string(ha, bc->build_paths[BuildPath_Output].basename);
+			pdb_path.name     = copy_string(ha, bc->build_paths[BuildPath_Output].name);
+			pdb_path.ext      = copy_string(ha, STR_LIT("pdb"));
+			bc->build_paths[BuildPath_PDB] = pdb_path;
+		}
+	}
+
 	// Do we have an extension? We might not if the output filename was supplied.
 	if (bc->build_paths[BuildPath_Output].ext.len == 0) {
 		if (build_context.metrics.os == TargetOs_windows || is_arch_wasm() || build_context.build_mode != BuildMode_Executable) {

src/linker.cpp

@@ -281,7 +281,7 @@ try_cross_linking:;
 				link_settings = gb_string_append_fmt(link_settings, " /ENTRY:mainCRTStartup");
 			}
 
-			if (build_context.pdb_filepath != "") {
+			if (build_context.build_paths[BuildPath_PDB].name != "") {
 				String pdb_path = path_to_string(heap_allocator(), build_context.build_paths[BuildPath_PDB]);
 				link_settings = gb_string_append_fmt(link_settings, " /PDB:\"%.*s\"", LIT(pdb_path));
 			}