I wonder if anyone has an idea about this thorny problem. I'm trying to create a package and thought I'd got something wrong, but have found the same behaviour happens with the "amp" package (version 0.6.1-1) and the "spherepack" package (version 3.3~a1-4), which suggests to me that the problem lies outside of the package itself. But I have very little idea how to track this bug down.
If I run sbuild: sbuild -s -A -d unstable spherepack_3.3~a1-4.dsc then the build starts OK, but when it comes to compiling the C sources (or maybe it's actually the Fortran sources - I don't know), I get the following: [...] building 'spherepack' extension compiling C sources C compiler: x86_64-linux-gnu-gcc -pthread -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O2 -Wall -g -ffile-prefix-map=/build/python3.9-euU3fN/python3.9-3.9.1=. -fstack-protector-strong -Wformat -Werror=format-security -g -fwrapv -O2 -g -O2 -ffile-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC creating build/temp.linux-x86_64-3.9/build creating build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9 creating build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9/Src creating build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9/build creating build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9/build/src.linux-x86_64-3.9 creating build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9/build/src.linux-x86_64-3.9/Src compile options: '-Ibuild/src.linux-x86_64-3.9/build/src.linux-x86_64-3.9/Src -I/usr/lib/python3/dist-packages/numpy/core/include -I/usr/include/python3.9 -c' error: [Errno 13] Permission denied An identical "Permission denied" error happens with the "amp" package as well, and also with the new package that I'm working on. However, with pbuilder: pbuilder build spherepack_3.3~a1-4.dsc I get a successful build, and the similar part of the output reads: [...] building 'spherepack' extension compiling C sources C compiler: x86_64-linux-gnu-gcc -pthread -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O2 -Wall -g -ffile-prefix-map=/build/python3.9-euU3fN/python3.9-3.9.1=. -fstack-protector-strong -Wformat -Werror=format-security -g -fwrapv -O2 -g -O2 -ffile-prefix-map=/build/spherepack-3.3~a1=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC compile options: '-Ibuild/src.linux-x86_64-3.9/build/src.linux-x86_64-3.9/Src -I/usr/lib/python3/dist-packages/numpy/core/include -I/usr/include/python3.9 -c' x86_64-linux-gnu-gcc -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions -Wl,-z,relro -g -fwrapv -O2 -Wl,-z,relro -g -O2 -ffile-prefix-map=/build/spherepack-3.3~a1=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9/Src/spherepackmodule.o build/temp.linux-x86_64-3.9/build/src.linux-x86_64-3.9/build/src.linux-x86_64-3.9/Src/fortranobject.o -L/build/spherepack-3.3~a1/Src -lsphere -o build/lib.linux-x86_64-3.9/spherepack.cpython-39-x86_64-linux-gnu.so running install_lib [...] They are so different, yet supposedly using essentially identical build environments. (They are also both using sid repositories.) If you have any idea why I might be seeing this behaviour, and what I might be able to do about it, that would be fantastic! Thanks! Julian