odb: fix segfault on invalid path in read_3dbx

src/odb/src/3dblox/3dblox.cpp

@@ -57,6 +57,10 @@ ThreeDBlox::ThreeDBlox(utl::Logger* logger, odb::dbDatabase* db, sta::Sta* sta)
 
 void ThreeDBlox::readDbv(const std::string& dbv_file)
 {
+  if (!std::filesystem::exists(dbv_file)) {
+    logger_->error(
+        utl::ODB, 541, "3DBV file does not exist: {}", dbv_file);
+  }
   read_files_.insert(std::filesystem::absolute(dbv_file).string());
   DbvParser parser(logger_);
   DbvData data = parser.parseFile(dbv_file);
@@ -174,6 +178,10 @@ void ThreeDBlox::buildChipNetsFromVerilog(dbChip* chip, const DbxData& data)
 
 void ThreeDBlox::readDbx(const std::string& dbx_file)
 {
+  if (!std::filesystem::exists(dbx_file)) {
+    logger_->error(
+        utl::ODB, 542, "3DBX file does not exist: {}", dbx_file);
+  }
   read_files_.insert(std::filesystem::absolute(dbx_file).string());
   DbxParser parser(logger_);
   DbxData data = parser.parseFile(dbx_file);

src/odb/src/db/dbBlock.cpp

@@ -2998,7 +2998,9 @@ dbBlock* dbBlock::create(dbChip* chip_, const char* name_, char hier_delimiter_)
   _dbBlock* top = chip->block_tbl_->create();
   top->initialize(chip, nullptr, name_, hier_delimiter_);
   chip->top_ = top->getOID();
-  top->dbu_per_micron_ = chip_->getTech()->getDbUnitsPerMicron();
+  if (chip_->getTech() != nullptr) {
+    top->dbu_per_micron_ = chip_->getTech()->getDbUnitsPerMicron();
+  }
   return (dbBlock*) top;
 }
 

src/odb/test/BUILD

@@ -186,6 +186,7 @@ COMPULSORY_TESTS = [
     "read_abstract_lef",
     "read_3dbv",
     "read_3dbx",
+    "read_3dbx-fail",
     "read_db",
     "read_def",
     "read_def58",
@@ -283,6 +284,7 @@ filegroup(
         "data/design58.def",
         "data/example.3dbv",
         "data/example.3dbx",
+        "data/fail.3dbx",
         "data/example.bmap",
         "data/example1.bmap",
         "data/example2.bmap",

src/odb/test/CMakeLists.txt

@@ -42,6 +42,7 @@ or_integration_tests(
     read_abstract_lef
     read_3dbv
     read_3dbx
+    read_3dbx-fail
     read_db
     read_def
     read_def58

src/odb/test/data/fail.3dbx

@@ -0,0 +1,9 @@
+Header:
+  version: "1.0"
+  unit: "micron"
+  precision: 2000
+  include:
+    - nonexistent_include.3dbv
+
+Design:
+  name: "TestDesign"

src/odb/test/read_3dbx-fail.ok

@@ -0,0 +1,3 @@
+Caught expected error: main file not found
+Caught expected error: include file not found
+pass

src/odb/test/read_3dbx-fail.tcl

@@ -0,0 +1,22 @@
+source "helpers.tcl"
+
+# Test that read_3dbx gives a proper error for a non-existent file
+# rather than segfaulting (regression test for issue #10082)
+
+# Test 1: Main file does not exist
+if { [catch {read_3dbx "nonexistent_file.3dbx"} err_msg] } {
+  puts "Caught expected error: main file not found"
+} else {
+  puts "FAIL: Expected an error for non-existent main file"
+  exit 1
+}
+
+# Test 2: Main file exists but references a non-existent include
+if { [catch {read_3dbx "data/fail.3dbx"} err_msg] } {
+  puts "Caught expected error: include file not found"
+} else {
+  puts "FAIL: Expected an error for non-existent include file"
+  exit 1
+}
+
+puts "pass"