https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110328
Bug ID: 110328
Summary: Module related optimization is too aggressive
Product: gcc
Version: 12.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: m-matti-a.lehtonen at iki dot fi
Target Milestone: ---
Created attachment 55375
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55375&action=edit
Example sources
When the module example (files test.cc and test2.cc) is compiles as
> g++-12 --std=c++20 -Wall -Wextra -Werror -pedantic -fmodules-ts -O1
> -DNDEBUG test2.cc test.cc
it generates the following error:
> In file included from test.cc:4,
> of module test, imported at test2.cc:5:
> In destructor ‘virtual std::bad_optional_access::~bad_optional_access()’,
> inlined from ‘virtual std::bad_optional_access::~bad_optional_access()’
> at > test2.cc:8:15:
> /usr/include/c++/12/optional:102:13: error: ‘this’ is used uninitialized
> [-Werror=uninitialized]
> 102 | virtual ~bad_optional_access() = default;
> | ^
> In file included from test2.cc:2:
> /usr/include/c++/12/optional: In destructor ‘virtual
> std::bad_optional_access::~bad_optional_access()’:
> /usr/include/c++/12/optional:102:13: note: ‘this’ was declared here
> 102 | virtual ~bad_optional_access() = default;
> | ^
If the if statement at test2.cc is uncommented, no error is generated.
If basically the same code (file test3.cc) is compiled without using modules,
no problem
> g++-12 --std=c++20 -Wall -Wextra -Werror -pedantic -O1 -DNDEBUG test3.cc
Exact version and system (Ubuntu 22.04.2 LTS)
> $ g++-12 --version
> g++-12 (Ubuntu 12.3.0-1ubuntu1~22.04) 12.3.0
