https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105544
--- Comment #6 from Fabian Vogt <fab...@ritter-vogt.de> --- I had a quick debugging session: The DMD lexer code doesn't really care about the size of the buffer and instead runs until it encounters either a 0 or 0x1A byte. The stdin read loop in d_parse_file doesn't explicitly 0-terminate the buffer, which means that it works randomly... With explicit termination it works: ~> echo -e "pragma(msg, int(__VERSION__));\0" | /usr/bin/gdc -x d - 2076 /usr/lib64/gcc/x86_64-suse-linux/11/../../../../x86_64-suse-linux/bin/ld: /usr/lib64/gcc/x86_64-suse-linux/11/../../../../lib64/Scrt1.o: in function `_start': /home/abuild/rpmbuild/BUILD/glibc-2.35/csu/../sysdeps/x86_64/start.S:103: undefined reference to `main' collect2: error: ld returned 1 exit status This also explains the huge amount of diagnostic messages, which are random based on the content past the module source buffer. It just runs until it encounters a terminator by accident. strace -k shows that the attempts to open "<stdin>" are actually caused by the printing of diagnostic messages itself, arguably a separate bug.
