scheme2c: ftbfs with GCC-5

Imported from Debian bug http://bugs.debian.org/778111:

Package: src:scheme2c
Version: 2012.10.14-1
Severity: normal
Tags: sid stretch
User: <email address hidden>
Usertags: ftbfs-gcc-5

Please keep this issue open in the bug tracker for the package it
was filed for. If a fix in another package is required, please
file a bug for the other package (or clone), and add a block in this
package. Please keep the issue open until the package can be built in
a follow-up test rebuild.

The package fails to build in a test rebuild on at least amd64 with
gcc-5/g++-5, but succeeds to build with gcc-4.9/g++-4.9. The
severity of this report may be raised before the stretch release.

The full build log can be found at:
http://people.debian.org/~doko/logs/gcc5-20150205/scheme2c_2012.10.14-1_unstable_gcc5.log
The last lines of the build log are at the end of this report.

To build with GCC 5, either set CC=gcc-5 CXX=g++-5 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t experimental install g++

Common build failures are C11 as the default C mode, new warnings
resulting in build failures with -Werror turned on, or new/dropped
symbols in Debian symbols files. For other C/C++ related build failures
see the porting guide at http://gcc.gnu.org/gcc-5/porting_to.html

[...]
mv Xs2ci s2ci
mv Xlibs2c.a libs2c.a
make[4]: Leaving directory '/«PKGBUILDDIR»/AMD64/scrt'
make[3]: Leaving directory '/«PKGBUILDDIR»/AMD64/scrt'
/usr/bin/make -C scsc port
make[3]: Entering directory '/«PKGBUILDDIR»/AMD64/scsc'
/usr/bin/make "CC=gcc" "CFLAGS=-Wall -O2 -finline-functions -fno-math-errno -frename-registers" "SCC=echo" Xs2ccomp s2ccomp
make[4]: Entering directory '/«PKGBUILDDIR»/AMD64/scsc'
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt main.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt closeana.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt lambdaexp.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt plist.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt transform.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt expform.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt readtext.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt miscexp.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt macros.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt compile.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt lap.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt gencode.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt callcode.c
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt lambdacode.c
lambdacode.c: In function 'lambdacode_procedure_2demit':
lambdacode.c:322:23: warning: variable 'X6' set but not used [-Wunused-but-set-variable]
               X8, X7, X6, X5, X4, X3, X2, X1;
                       ^
gcc -c -Wall -O2 -finline-functions -fno-math-errno -frename-registers -I../scrt misccode.c
gcc -o Xs2ccomp -Wall -O2 -finline-functions -fno-math-errno -frename-registers main.o closeana.o lambdaexp.o plist.o transform.o expform.o readtext.o miscexp.o macros.o compile.o lap.o gencode.o callcode.o lambdacode.o misccode.o ../scrt/libs2c.a -lm -lsigsegv
cp -pR Xs2ccomp s2ccomp
make[4]: Leaving directory '/«PKGBUILDDIR»/AMD64/scsc'
make[3]: Leaving directory '/«PKGBUILDDIR»/AMD64/scsc'
/usr/bin/make -C test autotest
make[3]: Entering directory '/«PKGBUILDDIR»/AMD64/test'
../scsc/Xs2cc -C -g test.sc
1193f39 SCRT7_IDENTIFIER Segfault:
test.sc:
***** Segfault -- Please tell the scheme->c maintainers!
***** Now we're going to try to print out a bracktrace, good luck!
make[3]: *** [test.c] Error 1
makefile:82: recipe for target 'test.c' failed
make[3]: Leaving directory '/«PKGBUILDDIR»/AMD64/test'
make[2]: *** [port] Error 2
makefile:10: recipe for target 'port' failed
make[2]: Leaving directory '/«PKGBUILDDIR»/AMD64'
make[1]: *** [override_dh_auto_build] Error 2
debian/rules:35: recipe for target 'override_dh_auto_build' failed
make[1]: Leaving directory '/«PKGBUILDDIR»'
make: *** [build-arch] Error 2
debian/rules:20: recipe for target 'build-arch' failed
dpkg-buildpackage: error: debian/rules build-arch gave error exit status 2