[PATCH v2 21/21] reader/symtab: Improve handling for suppressed aliases

[Matthias Maennich <maennich@google.com>]

When reading from XML with a symbol whitelist that leads to suppression
of aliased symbols, abidiff would hit an assertion and crash when
looking up the aliased symbol due to it being suppressed. In the new
symtab reader we can still suppress a symbol without removing it from
the lookup. Make use of that property to fix this bug.

A test has been added for this as well.

	* src/abg-reader.cc (build_elf_symbol): Improve handling of
	suppressed aliased symbols when reading from XML.
	* src/abg-symtab-reader.cc (load): Likewise.
	* tests/data/Makefile.am: Add new test data files.
	* tests/data/test-abidiff-exit/test-missing-alias-report.txt: New test file.
	* tests/data/test-abidiff-exit/test-missing-alias.abi: Likewise.
	* tests/data/test-abidiff-exit/test-missing-alias.suppr: Likewise.
	* tests/test-abidiff-exit.cc: Add support for whitelists and add
	new testcase.

Reviewed-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Matthias Maennich <maennich@google.com>
---
 src/abg-reader.cc                                |  7 +++++--
 src/abg-symtab-reader.cc                         | 16 ++++++++++++++--
 tests/data/Makefile.am                           |  3 +++
 .../test-missing-alias-report.txt                |  0
 .../test-abidiff-exit/test-missing-alias.abi     | 12 ++++++++++++
 .../test-abidiff-exit/test-missing-alias.suppr   |  4 ++++
 tests/test-abidiff-exit.cc                       |  9 +++++++++
 7 files changed, 47 insertions(+), 4 deletions(-)
 create mode 100644 tests/data/test-abidiff-exit/test-missing-alias-report.txt
 create mode 100644 tests/data/test-abidiff-exit/test-missing-alias.abi
 create mode 100644 tests/data/test-abidiff-exit/test-missing-alias.suppr

diff --git a/src/abg-reader.cc b/src/abg-reader.cc
index 3f636d00f9b8..d71e2d43503a 100644
--- a/src/abg-reader.cc
+++ b/src/abg-reader.cc
@@ -2850,7 +2850,8 @@ build_elf_symbol(read_context& ctxt, const xmlNodePtr node,
 
   elf_symbol::version version(version_string, is_default_version);
 
-  if (drop_if_suppressed && suppr::is_elf_symbol_suppressed(ctxt, name, type))
+  const bool is_suppressed = suppr::is_elf_symbol_suppressed(ctxt, name, type);
+  if (drop_if_suppressed && is_suppressed)
     return elf_symbol_sptr();
 
   const environment* env = ctxt.get_environment();
@@ -2860,6 +2861,8 @@ build_elf_symbol(read_context& ctxt, const xmlNodePtr node,
 					 version, visibility,
 					 /*is_linux_string_cst=*/false);
 
+  e->set_is_suppressed(is_suppressed);
+
   if (crc != 0)
     e->set_crc(crc);
 
@@ -2950,7 +2953,7 @@ build_elf_symbol_db(read_context& ctxt,
   elf_symbol_sptr sym;
   for (xmlNodePtr n = node->children; n; n = n->next)
     {
-      if ((sym = build_elf_symbol(ctxt, n, /*drop_if_suppress=*/true)))
+      if ((sym = build_elf_symbol(ctxt, n, /*drop_if_suppress=*/false)))
 	{
 	  id_sym_map[sym->get_id_string()] = sym;
 	  xml_node_ptr_elf_symbol_map[n] = sym;
diff --git a/src/abg-symtab-reader.cc b/src/abg-symtab-reader.cc
index c50c0f643386..424817106e70 100644
--- a/src/abg-symtab-reader.cc
+++ b/src/abg-symtab-reader.cc
@@ -361,7 +361,13 @@ symtab::load_(string_elf_symbols_map_sptr function_symbol_map,
 	     end = function_symbol_map->end();
 	 it != end; ++it)
       {
-	symbols_.insert(symbols_.end(), it->second.begin(), it->second.end());
+	for (elf_symbols::const_iterator sym_it = it->second.begin(),
+					 sym_end = it->second.end();
+	     sym_it != sym_end; ++sym_it)
+	  {
+	    if (!(*sym_it)->is_suppressed())
+	      symbols_.push_back(*sym_it);
+	  }
 	ABG_ASSERT(name_symbol_map_.insert(*it).second);
       }
 
@@ -371,7 +377,13 @@ symtab::load_(string_elf_symbols_map_sptr function_symbol_map,
 	     end = variables_symbol_map->end();
 	 it != end; ++it)
       {
-	symbols_.insert(symbols_.end(), it->second.begin(), it->second.end());
+	for (elf_symbols::const_iterator sym_it = it->second.begin(),
+					 sym_end = it->second.end();
+	     sym_it != sym_end; ++sym_it)
+	  {
+	    if (!(*sym_it)->is_suppressed())
+	      symbols_.push_back(*sym_it);
+	  }
 	ABG_ASSERT(name_symbol_map_.insert(*it).second);
       }
 
diff --git a/tests/data/Makefile.am b/tests/data/Makefile.am
index f39a6d427b1d..bcfc3796d0bc 100644
--- a/tests/data/Makefile.am
+++ b/tests/data/Makefile.am
@@ -161,6 +161,9 @@ test-abidiff-exit/test-fun-param-v0.o \
 test-abidiff-exit/test-fun-param-v1.abi \
 test-abidiff-exit/test-fun-param-v1.c \
 test-abidiff-exit/test-fun-param-v1.o \
+test-abidiff-exit/test-missing-alias-report.txt \
+test-abidiff-exit/test-missing-alias.abi \
+test-abidiff-exit/test-missing-alias.suppr \
 \
 test-diff-dwarf/test0-v0.cc		\
 test-diff-dwarf/test0-v0.o			\
diff --git a/tests/data/test-abidiff-exit/test-missing-alias-report.txt b/tests/data/test-abidiff-exit/test-missing-alias-report.txt
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/tests/data/test-abidiff-exit/test-missing-alias.abi b/tests/data/test-abidiff-exit/test-missing-alias.abi
new file mode 100644
index 000000000000..07a13f5e6d15
--- /dev/null
+++ b/tests/data/test-abidiff-exit/test-missing-alias.abi
@@ -0,0 +1,12 @@
+<abi-corpus path='test.so' soname='test.so'>
+  <elf-function-symbols>
+    <elf-symbol name='__foo' type='func-type' binding='global-binding' visibility='default-visibility' alias='foo' is-defined='yes'/>
+    <elf-symbol name='foo' type='func-type' binding='weak-binding' visibility='default-visibility' is-defined='yes'/>
+  </elf-function-symbols>
+  <abi-instr version='1.0' address-size='64' path='test.c' language='LANG_C89'>
+    <type-decl name='void' id='48b5725f'/>
+    <function-decl name='__foo' mangled-name='__foo' filepath='test.c' line='8' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='__foo'>
+      <return type-id='48b5725f'/>
+    </function-decl>
+  </abi-instr>
+</abi-corpus>
diff --git a/tests/data/test-abidiff-exit/test-missing-alias.suppr b/tests/data/test-abidiff-exit/test-missing-alias.suppr
new file mode 100644
index 000000000000..bcebae43a350
--- /dev/null
+++ b/tests/data/test-abidiff-exit/test-missing-alias.suppr
@@ -0,0 +1,4 @@
+[suppress_function]
+  symbol_name_not_regexp = ^__foo$
+  drop = true
+
diff --git a/tests/test-abidiff-exit.cc b/tests/test-abidiff-exit.cc
index 4d9c19437e60..772baa78cf91 100644
--- a/tests/test-abidiff-exit.cc
+++ b/tests/test-abidiff-exit.cc
@@ -212,6 +212,15 @@ InOutSpec in_out_specs[] =
     "data/test-abidiff-exit/test-fun-param-report.txt",
     "output/test-abidiff-exit/test-fun-param-report.txt"
   },
+  {
+    "data/test-abidiff-exit/test-missing-alias.abi",
+    "data/test-abidiff-exit/test-missing-alias.abi",
+    "data/test-abidiff-exit/test-missing-alias.suppr",
+    "",
+    abigail::tools_utils::ABIDIFF_OK,
+    "data/test-abidiff-exit/test-missing-alias-report.txt",
+    "output/test-abidiff-exit/test-missing-alias-report.txt"
+  },
   {0, 0, 0 ,0,  abigail::tools_utils::ABIDIFF_OK, 0, 0}
 };
 
-- 
2.27.0.212.ge8ba1cc988-goog