memory corruption in pic

I tried building the groff-1.25.0.rc1 with clang's ASAN.
The next error (during "make -k check"):

  GROFF    contrib/mom/examples/slide-demo.pdf
=================================================================
==851776==ERROR: AddressSanitizer: alloc-dealloc-mismatch (malloc vs operator delete []) on 0x6d23571e0330
    #0 0x587f8b4ae9ed in operator delete[](void*) /home/runner/work/llvm-project/llvm-project/compiler-rt/lib/asan/asan_new_delete.cpp:179:46
    #1 0x587f8b4f8b0f in output::~output() /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/object.cpp:47:3
    #2 0x587f8b5345a4 in common_output::~common_output() /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/common.h:20:7
    #3 0x587f8b53c614 in simple_output::~simple_output() /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/troff.cpp:37:7
    #4 0x587f8b53757a in troff_output::~troff_output() /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/troff.cpp:276:1
    #5 0x587f8b5375d4 in troff_output::~troff_output() /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/troff.cpp:274:1
    #6 0x587f8b4f8423 in main /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/main.cpp:698:3
    #7 0x710357e2a600 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:59:16
    #8 0x710357e2a717 in __libc_start_main csu/../csu/libc-start.c:360:3
    #9 0x587f8b3c5b04 in _start (/build/groff-1.25.0.rc1/build-64-clang/pic+0x80b04)

0x6d23571e0330 is located 0 bytes inside of 7-byte region [0x6d23571e0330,0x6d23571e0337)
allocated by thread T0 here:
    #0 0x587f8b46aee4 in malloc /home/runner/work/llvm-project/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:67:3
    #1 0x587f8b54c677 in strsave(char const*) /build/groff-1.25.0.rc1/build-64-clang/../src/libs/libgroff/strsave.cpp:36:33
    #2 0x587f8b4f8d41 in output::set_args(char const*) /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/object.cpp:62:12
    #3 0x587f8b4f7356 in do_picture(_IO_FILE*) /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/main.cpp:297:10
    #4 0x587f8b4f5f4f in do_file(char const*) /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/main.cpp:395:2
    #5 0x587f8b4f8241 in main /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/main.cpp:691:7
    #6 0x710357e2a600 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:59:16
    #7 0x710357e2a717 in __libc_start_main csu/../csu/libc-start.c:360:3
    #8 0x587f8b3c5b04 in _start (/build/groff-1.25.0.rc1/build-64-clang/pic+0x80b04)

SUMMARY: AddressSanitizer: alloc-dealloc-mismatch /build/groff-1.25.0.rc1/build-64-clang/../src/preproc/pic/object.cpp:47:3 in output::~output()
==851776==HINT: if you don't care about these errors you may set ASAN_OPTIONS=alloc_dealloc_mismatch=0
==851776==ABORTING
/build/groff-1.25.0.rc1/build-64-clang/groff: error: pic: Aborted

Explanation:
malloc() pairs with free().
new[] pairs with delete[].

Bruno