Add options to make elf symbol changes as warnings.

Some elf symbols in the .dynsym table of an .so file may not be present
in the headers exported by a shared library. We must still know about
these changes. Therefore, add options to make notifications about
these changes warnings instead of errors.

Bug: 62060883

Test: tests/test.py pass

Change-Id: Ic0cbad3370597c251f9e2c0f2b8cbb089aed155f

vndk/tools/header-checker/header-abi-diff/src/header_abi_diff.cpp

@@ -51,6 +51,12 @@ static llvm::cl::opt<bool> advice_only(
     "advice-only", llvm::cl::desc("Advisory mode only"), llvm::cl::Optional,
     llvm::cl::cat(header_checker_category));
 
+static llvm::cl::opt<bool> elf_unreferenced_symbol_errors(
+    "elf-unreferenced-symbol-errors",
+    llvm::cl::desc("Display erors on removal of elf symbols, unreferenced by"
+                   "metadata in exported headers."),
+    llvm::cl::Optional, llvm::cl::cat(header_checker_category));
+
 static llvm::cl::opt<bool> check_all_apis(
     "check-all-apis",
     llvm::cl::desc("All apis, whether referenced or not, by exported symbols in"
@@ -66,6 +72,12 @@ static llvm::cl::opt<bool> allow_extensions(
     llvm::cl::desc("Do not return a non zero status on extensions"),
     llvm::cl::Optional, llvm::cl::cat(header_checker_category));
 
+static llvm::cl::opt<bool> allow_unreferenced_elf_symbol_changes(
+    "allow-unreferenced-elf-symbol-changes",
+    llvm::cl::desc("Do not return a non zero status on changes to elf symbols"
+                   "not referenced by metadata in exported headers"),
+    llvm::cl::Optional, llvm::cl::cat(header_checker_category));
+
 static llvm::cl::opt<bool> allow_unreferenced_changes(
     "allow-unreferenced-changes",
     llvm::cl::desc("Do not return a non zero status on changes to data"
@@ -102,11 +114,21 @@ int main(int argc, const char **argv) {
   std::string status_str = "";
   std::string unreferenced_change_str = "";
   std::string error_or_warning_str = "\033[36;1mwarning: \033[0m";
-
+  switch (status) {
-  if (status == abi_util::CompatibilityStatusIR::Incompatible) {
+    case abi_util::CompatibilityStatusIR::Incompatible:
       error_or_warning_str = "\033[31;1merror: \033[0m";
       status_str = "INCOMPATIBLE CHANGES";
-  } else if (status & abi_util::CompatibilityStatusIR::Extension) {
+      break;
+    case abi_util::CompatibilityStatusIR::ElfIncompatible:
+      if (elf_unreferenced_symbol_errors) {
+        error_or_warning_str = "\033[31;1merror: \033[0m";
+      }
+      status_str = "ELF Symbols not referenced by exported headers removed";
+      break;
+    default:
+      break;
+  }
+  if (status & abi_util::CompatibilityStatusIR::Extension) {
     status_str = "EXTENDING CHANGES";
   }
   if (status & abi_util::CompatibilityStatusIR::UnreferencedChanges) {
@@ -114,7 +136,6 @@ int main(int argc, const char **argv) {
     unreferenced_change_str += " not directly referenced by exported symbols.";
     unreferenced_change_str += " This MIGHT be an ABI breaking change due to";
     unreferenced_change_str += " internal typecasts.";
-
   }
   if (!suppress_local_warnings && status) {
     llvm::errs() << "******************************************************\n"
@@ -132,11 +153,10 @@ int main(int argc, const char **argv) {
   if ((allow_extensions &&
       (status & abi_util::CompatibilityStatusIR::Extension)) ||
       (allow_unreferenced_changes &&
-      (status & abi_util::CompatibilityStatusIR::UnreferencedChanges))) {
+      (status & abi_util::CompatibilityStatusIR::UnreferencedChanges)) ||
-    return abi_util::CompatibilityStatusIR::Compatible;
+      (allow_unreferenced_elf_symbol_changes &&
-  }
+      (status & abi_util::CompatibilityStatusIR::ElfIncompatible)) ||
-
+      advice_only) {
-  if (advice_only) {
     return abi_util::CompatibilityStatusIR::Compatible;
   }
 

vndk/tools/header-checker/header-abi-util/include/ir_representation.h

@@ -29,7 +29,8 @@ enum CompatibilityStatusIR {
   Compatible = 0,
   UnreferencedChanges = 1,
   Extension = 4,
-  Incompatible = 8
+  Incompatible = 8,
+  ElfIncompatible = 16
 };
 
 static inline CompatibilityStatusIR operator|(CompatibilityStatusIR f,

vndk/tools/header-checker/header-abi-util/src/ir_representation_protobuf.cpp

@@ -1020,19 +1020,20 @@ CompatibilityStatusIR ProtobufIRDiffDumper::GetCompatibilityStatusIR() {
       diff_tu_->function_diffs().size() != 0 ||
       diff_tu_->global_var_diffs().size() != 0 ||
       diff_tu_->enum_type_diffs().size() != 0 ||
-      diff_tu_->record_type_diffs().size() != 0 ||
+      diff_tu_->record_type_diffs().size() != 0) {
-      diff_tu_->removed_elf_functions().size() != 0 ||
-      diff_tu_->removed_elf_objects().size() != 0) {
     return CompatibilityStatusIR::Incompatible;
   }
 
+  if(diff_tu_->removed_elf_functions().size() != 0 ||
+     diff_tu_->removed_elf_objects().size() != 0) {
+    return CompatibilityStatusIR::ElfIncompatible;
+  }
+
   CompatibilityStatusIR combined_status = CompatibilityStatusIR::Compatible;
 
   if (diff_tu_->enum_type_extension_diffs().size() != 0 ||
       diff_tu_->functions_added().size() != 0 ||
-      diff_tu_->global_vars_added().size() !=0 ||
+      diff_tu_->global_vars_added().size() != 0) {
-      diff_tu_->added_elf_functions().size() != 0 ||
-      diff_tu_->added_elf_objects().size() != 0) {
     combined_status = combined_status | CompatibilityStatusIR::Extension;
   }