In the attached program, Beta::~Beta() is noreturn. gcc is smart enough to figure out the noreturn in DeltaOne and DeltaTwo, but forgets about noreturn in DeltaThree and issues an unwanted warning.
[EMAIL PROTECTED]:~/exp-non-void$ /home/mec/gcc-4.1.1/install/bin/g++ -Wall -c z4.cc z4.cc: In function 'bool DeltaTwo(bool)': z4.cc:28: warning: unused variable 'b2' z4.cc: In function 'bool DeltaThree(bool)': z4.cc:42: warning: control reaches end of non-void function [EMAIL PROTECTED]:~/exp-non-void$ /home/mec/gcc-4.2.1/install/bin/g++ -Wall -c z4.cc z4.cc: In function 'bool DeltaTwo(bool)': z4.cc:28: warning: unused variable 'b2' z4.cc: In function 'bool DeltaThree(bool)': z4.cc:42: warning: control reaches end of non-void function [EMAIL PROTECTED]:~/exp-non-void$ /home/mec/gcc-4.3-20070914/install/bin/g++ -Wall -c z4.cc z4.cc: In function 'bool DeltaTwo(bool)': z4.cc:28: warning: unused variable 'b2' z4.cc: In function 'bool DeltaThree(bool)': z4.cc:42: warning: control reaches end of non-void function -- Summary: gcc forgets about noreturn in this code Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: mec at google dot com GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33752