[Bug ada/39502] New: Unexpected uninitialized warning

[alex at segv dot de]

By compiling the attached files I get a warning like this:
./some_package-some_seperate_package.adb: In function
'SOME_PACKAGE.SOME_SEPERATE_PACKAGE.GET_STATE':
./some_package-some_seperate_package.adb:22: warning:
'state_infos.current_state' is used uninitialized in this function

but I think there should be no warning at all.

It seems it takes several conditions to trigger this warning: 
 - a record variable as a out parameter
 - the code most be in a seperate package
 - The flags -Wuninitialized and -fPIC need to be set

I can reproduce this on 4.3.3 and 4.3.0 (and probably more versions).


$ gcc -v -save-temps -c -I./ -Wuninitialized -fPIC  -O2 ./some_package.adb
Using built-in specs.
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.3.3-5ubuntu4'
--with-bugurl=file:///usr/share/doc/gcc-4.3/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --enable-shared
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --enable-nls --with-gxx-include-dir=/usr/include/c++/4.3
--program-suffix=-4.3 --enable-clocale=gnu --enable-libstdcxx-debug
--enable-objc-gc --enable-mpfr --with-tune=generic --enable-checking=release
--build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4)
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-c' '-I./' '-Wuninitialized' '-fPIC'
'-O2' '-mtune=generic'
 /usr/lib/gcc/x86_64-linux-gnu/4.3.3/gnat1 -I./ -quiet -dumpbase
some_package.adb -O2 -Wuninitialized -fPIC -mtune=generic ./some_package.adb -o
some_package.s
./some_package-some_seperate_package.adb: In function
'SOME_PACKAGE.SOME_SEPERATE_PACKAGE.GET_STATE':
./some_package-some_seperate_package.adb:22: warning:
'state_infos.current_state' is used uninitialized in this function
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-c' '-I./' '-Wuninitialized' '-fPIC'
'-O2' '-mtune=generic'
 as -V -Qy -o some_package.o some_package.s
GNU assembler version 2.19.1 (x86_64-linux-gnu) using BFD version (GNU Binutils
for Ubuntu) 2.19.1
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/4.3.3/:/usr/lib/gcc/x86_64-linux-gnu/4.3.3/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/4.3.3/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/4.3.3/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/4.3.3/:/usr/lib/gcc/x86_64-linux-gnu/4.3.3/:/usr/lib/gcc/x86_64-linux-gnu/4.3.3/../../../../lib/:/lib/../lib/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/4.3.3/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-c' '-I./' '-Wuninitialized' '-fPIC'
'-O2' '-mtune=generic'


Regards
Alexander Elbs.


-- 
           Summary: Unexpected uninitialized warning
           Product: gcc
           Version: 4.3.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ada
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: alex at segv dot de


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39502