[Bug tree-optimization/126739] New: [16 regression] false positive -Warray-bounds

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126739

            Bug ID: 126739
           Summary: [16 regression] false positive -Warray-bounds
           Product: gcc
           Version: 16.1.1
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: [email protected]
  Target Milestone: ---
            Target: riscv64-*-*

Created attachment 65277
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=65277&action=edit
json_schema_converter.ii

$ gcc-16 -O2 -Warray-bounds -S json_schema_converter.ii
json_schema_converter.ii:61:3: warning: access declarations are deprecated in
favor of using-declarations; suggestion: add the ‘using’ keyword [-Wdeprecated]
   61 |   _Base::_Base;
      |   ^~~~~
json_schema_converter.ii:68:3: warning: access declarations are deprecated in
favor of using-declarations; suggestion: add the ‘using’ keyword [-Wdeprecated]
   68 |   _Base::_Base;
      |   ^~~~~
json_schema_converter.ii:75:3: warning: access declarations are deprecated in
favor of using-declarations; suggestion: add the ‘using’ keyword [-Wdeprecated]
   75 |   _Base::_Base;
      |   ^~~~~
json_schema_converter.ii:82:3: warning: access declarations are deprecated in
favor of using-declarations; suggestion: add the ‘using’ keyword [-Wdeprecated]
   82 |   _Base::_Base;
      |   ^~~~~
In member function ‘char* Trans_NS___cxx11_basic_string::c_str() const’,
    inlined from ‘virtual char* xgrammar::<unnamed struct>::what() const’ at
json_schema_converter.ii:112:50,
    inlined from ‘xgrammar::{anonymous}::SchemaErrorType xgrammar::{anonymous}:
ParseInteger()’ at json_schema_converter.ii:130:23,
    inlined from ‘void xgrammar::JSONSchemaToEBNF()’ at
json_schema_converter.ii:134:39:
json_schema_converter.ii:23:32: warning: array subscript 2 is outside array
bounds of ‘xgrammar::Result<long int,
xgrammar::TypedError<xgrammar::{anonymous}::SchemaErrorType> > [1]’
[-Warray-bounds=]
   23 |   char *c_str() const { return _M_p; }
      |                                ^~~~
json_schema_converter.ii: In function ‘void xgrammar::JSONSchemaToEBNF()’:
json_schema_converter.ii:128:4: note: at offset 32 into object ‘<anonymous>’ of
size 8
  126 |   [](int) -> Result<long, TypedError<SchemaErrorType>> {
      |   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  127 |     return ParseInteger_val;
      |     ~~~~~~~~~~~~~~~~~~~~~~~~
  128 |   }(ParseInteger___trans_tmp_1)
      |   ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~