Fix size test build on gcc11 (#17905)

lucylq · Github Executorch · web-flow · commit 411061fcb66c · 2026-03-06T14:24:34.000-08:00
### Summary

Fix size-test on gcc11 (not a binary size improvement)

It fails with stringop-overread from flatbuffer. gcc-9 doesn't have this
and doesn't throw error.
```
In static member function ‘static constexpr std::size_t std::char_traits&lt;char&gt;::length(const char_type*)’,
    inlined from ‘constexpr std::basic_string_view&lt;_CharT, _Traits&gt;::basic_string_view(const _CharT*) [with _CharT = char; _Traits = std::char_traits&lt;char&gt;]’ at /usr/include/c++/11/string_view:132:35,
    inlined from ‘executorch::runtime::Result&lt;void*&gt; executorch::runtime::deserialization::getTensorDataPtr(const executorch_flatbuffer::Tensor*, const executorch::runtime::Program*, size_t, executorch::runtime::HierarchicalAllocator*, const executorch::runtime::NamedDataMap*, executorch::runtime::Span&lt;executorch::runtime::deserialization::NamedData&gt;)’ at /data/users/lfq/binary-size/executorch/runtime/executor/tensor_parser_exec_aten.cpp:218:41:
/usr/include/c++/11/bits/char_traits.h:399:32: error: ‘long unsigned int __builtin_strlen(const char*)’ reading 1 or more bytes from a region of size 0 [-Werror=stringop-overread]
  399 |         return __builtin_strlen(__s);
      |                ~~~~~~~~~~~~~~~~^~~~~
In file included from /data/users/lfq/binary-size/executorch/../executorch/runtime/executor/tensor_parser.h:21,
                 from /data/users/lfq/binary-size/executorch/runtime/executor/tensor_parser_exec_aten.cpp:9:
/data/users/lfq/binary-size/executorch/cmake-out/schema/include/executorch/schema/program_generated.h: In function ‘executorch::runtime::Result&lt;void*&gt; executorch::runtime::deserialization::getTensorDataPtr(const executorch_flatbuffer::Tensor*, const executorch::runtime::Program*, size_t, executorch::runtime::HierarchicalAllocator*, const executorch::runtime::NamedDataMap*, executorch::runtime::Span&lt;executorch::runtime::deserialization::NamedData&gt;)’:
/data/users/lfq/binary-size/executorch/cmake-out/schema/include/executorch/schema/program_generated.h:568:8: note: at offset 5 into source object ‘executorch_flatbuffer::ExtraTensorInfo::&lt;anonymous&gt;’ of size 1
  568 | struct ExtraTensorInfo FLATBUFFERS_FINAL_CLASS : private ::flatbuffers::Table {
```

### Test plan
Flatbuffer should be ok - add -Wno-stringop-overread to suppress the
error. Use pragma because adding it in CXX_ARGS causes a failure, as
gcc-9 doesn't recognize it and -Werror is enabled.

size results after stripping
```
sh test/build_size_test.sh 

(executorch) [lfq@devvm11764.nha0 /data/users/lfq/binary-size/executorch (binary-size)]$ ls -la cmake-out/test/size_test_all_ops
-rwxr-xr-x 1 lfq users 1670416 Mar  4 22:37 cmake-out/test/size_test_all_ops

(executorch) [lfq@devvm11764.nha0 /data/users/lfq/binary-size/executorch (binary-size)]$ ls -la cmake-out/test/size_test
-rwxr-xr-x 1 lfq users 56240 Mar  4 22:38 cmake-out/test/size_test
```

---------

Co-authored-by: Github Executorch &lt;github_executorch@arm.com&gt;
diff --git a/runtime/executor/tensor_parser_exec_aten.cpp b/runtime/executor/tensor_parser_exec_aten.cpp
@@ -159,6 +159,14 @@ NamedData* get_data_by_key(const char* key, Span<NamedData> entries) {
   return nullptr;
 }
 
+// Suppress a GCC 11 false positive -Wstringop-overread triggered by
+// flatbuffers' GetPointer inlining into string_view construction.
+// Guarded to GCC >= 11 since the warning doesn't exist on older GCC or Clang.
+#if defined(__GNUC__) && !defined(__clang__) && __GNUC__ >= 11
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstringop-overread"
+#endif
+
 ET_NODISCARD Result<void*> getTensorDataPtr(
     const executorch_flatbuffer::Tensor* s_tensor,
     const Program* program,
@@ -259,6 +267,10 @@ ET_NODISCARD Result<void*> getTensorDataPtr(
   }
 }
 
+#if defined(__GNUC__) && !defined(__clang__) && __GNUC__ >= 11
+#pragma GCC diagnostic pop
+#endif
+
 } // namespace deserialization
 } // namespace ET_RUNTIME_NAMESPACE
 } // namespace executorch
