Description of problem:

I am building Audacity using all the Fedora flags (including the LTO flags), and I am receiving a very strange error. One of the shared libraries that it builds contains two files (a header and its C++ source) which are the following:


Meter.h begin code>>>

/*!********************************************************************

Audacity: A Digital Audio Editor

@file Meter.h

Paul Licameli split from MeterPanelBase.h

**********************************************************************/

#ifndef __AUDACITY_METER__
#define __AUDACITY_METER__

//! AudioIO uses this to send sample buffers for real-time display updates
class AUDIO_DEVICES_API Meter /* not final */
{
public:
   virtual ~Meter();

   virtual void Clear() = 0;
   virtual void Reset(double sampleRate, bool resetClipping) = 0;
   virtual void UpdateDisplay(unsigned numChannels,
                      unsigned long numFrames, const float *sampleData) = 0;
   virtual bool IsMeterDisabled() const = 0;
   virtual float GetMaxPeak() const = 0;
   virtual bool IsClipping() const = 0;
   virtual int GetDBRange() const = 0;
};

#endif

<<< end code

Meter.cpp begin code >>>

/*!********************************************************************

Audacity: A Digital Audio Editor

@file Meter.cpp

Paul Licameli split from MeterPanelBase.cpp

**********************************************************************/

#include "Meter.h"

#include <string>

Meter::~Meter()
{
}

<<< end code


When building these and linking them against a few other C++ files into the shared library, GCC throws this error and terminates:

[ 44%] Linking CXX shared library ../../shared/Debug/lib-audio-devices.so
lto1: fatal error: bytecode stream in file ‘CMakeFiles/lib-audio-devices.dir/Meter.cpp.o’ generated with LTO version 11.0 instead of the expected 11.2
compilation terminated.
lto-wrapper: fatal error: /usr/bin/c++ returned 1 exit status
compilation terminated.
/usr/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status
make[2]: *** [libraries/lib-audio-devices/CMakeFiles/lib-audio-devices.dir/build.make:159: shared/Debug/lib-audio-devices.so] Error 1
make[1]: *** [CMakeFiles/Makefile2:1337: libraries/lib-audio-devices/CMakeFiles/lib-audio-devices.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....


If I just add #include <string> inside Meter.cpp, then GCC no longer throws this LTO error and the compilation succeeds.


Version-Release number of selected component (if applicable):

gcc-11.2.1-9.fc35.x86_64
gcc-c++-11.2.1-9.fc35.x86_64