openjpeg doesn't install a relocatable shared lib on macOS

[SpaceIm]

openjpeg CMakeLists unconditionally (and surprisingly) changes INSTALL_NAME_DIR property of openjp2 target if Apple:

openjpeg/CMakeLists.txt

Line 159 in a5c95cf

list(APPEND OPENJPEG_LIBRARY_PROPERTIES INSTALL_NAME_DIR "${CMAKE_INSTALL_PREFIX}/${OPENJPEG_INSTALL_LIB_DIR}")

This leads to a hardcoded path in installed shared lib, which shouldn't be the default behavior for sure. Default CMake behavior is to install relocatable runtimes on macOS with @rpath/<libname>, if https://cmake.org/cmake/help/v3.0/policy/CMP0042.html is NEW (which is the case in openjpeg CMakeLists, this is why it's very surprising to see this hardcoded INSTALL_NAME).

I would expect this after running otool -l libopenjp2.2.4.0.dylib (relevant part in this output is name @rpath/libopenjp2.7.dylib (offset 24)):

libopenjp2.2.4.0.dylib:
Load command 0
      cmd LC_SEGMENT_64
  cmdsize 472
  segname __TEXT
   vmaddr 0x0000000000000000
   vmsize 0x0000000000054000
  fileoff 0
 filesize 344064
  maxprot 0x00000005
 initprot 0x00000005
   nsects 5
    flags 0x0
Section
  sectname __text
   segname __TEXT
      addr 0x00000000000043e0
      size 0x0000000000048181
    offset 17376
     align 2^4 (16)
    reloff 0
    nreloc 0
     flags 0x80000400
 reserved1 0
 reserved2 0
Section
  sectname __stubs
   segname __TEXT
      addr 0x000000000004c562
      size 0x0000000000000102
    offset 312674
     align 2^1 (2)
    reloff 0
    nreloc 0
     flags 0x80000408
 reserved1 0 (index into indirect symbol table)
 reserved2 6 (size of stubs)
Section
  sectname __const
   segname __TEXT
      addr 0x000000000004c670
      size 0x000000000000162c
    offset 312944
     align 2^4 (16)
    reloff 0
    nreloc 0
     flags 0x00000000
 reserved1 0
 reserved2 0
Section
  sectname __cstring
   segname __TEXT
      addr 0x000000000004dca0
      size 0x0000000000005ffa
    offset 318624
     align 2^4 (16)
    reloff 0
    nreloc 0
     flags 0x00000002
 reserved1 0
 reserved2 0
Section
  sectname __unwind_info
   segname __TEXT
      addr 0x0000000000053c9c
      size 0x0000000000000360
    offset 343196
     align 2^2 (4)
    reloff 0
    nreloc 0
     flags 0x00000000
 reserved1 0
 reserved2 0
Load command 1
      cmd LC_SEGMENT_64
  cmdsize 232
  segname __DATA_CONST
   vmaddr 0x0000000000054000
   vmsize 0x0000000000004000
  fileoff 344064
 filesize 16384
  maxprot 0x00000003
 initprot 0x00000003
   nsects 2
    flags 0x10
Section
  sectname __got
   segname __DATA_CONST
      addr 0x0000000000054000
      size 0x0000000000000168
    offset 344064
     align 2^3 (8)
    reloff 0
    nreloc 0
     flags 0x00000006
 reserved1 43 (index into indirect symbol table)
 reserved2 0
Section
  sectname __const
   segname __DATA_CONST
      addr 0x0000000000054170
      size 0x0000000000000b20
    offset 344432
     align 2^4 (16)
    reloff 0
    nreloc 0
     flags 0x00000000
 reserved1 0
 reserved2 0
Load command 2
      cmd LC_SEGMENT_64
  cmdsize 72
  segname __LINKEDIT
   vmaddr 0x0000000000058000
   vmsize 0x0000000000008000
  fileoff 360448
 filesize 25072
  maxprot 0x00000001
 initprot 0x00000001
   nsects 0
    flags 0x0
Load command 3
          cmd LC_ID_DYLIB
      cmdsize 56
         name @rpath/libopenjp2.7.dylib (offset 24)
   time stamp 1 Thu Jan  1 01:00:01 1970
      current version 2.4.0
compatibility version 7.0.0
Load command 4
      cmd LC_DYLD_CHAINED_FIXUPS
  cmdsize 16
  dataoff 360448
 datasize 816
Load command 5
      cmd LC_DYLD_EXPORTS_TRIE
  cmdsize 16
  dataoff 361264
 datasize 5512
Load command 6
     cmd LC_SYMTAB
 cmdsize 24
  symoff 367496
   nsyms 469
  stroff 375352
 strsize 10168
Load command 7
            cmd LC_DYSYMTAB
        cmdsize 80
      ilocalsym 0
      nlocalsym 165
     iextdefsym 165
     nextdefsym 259
      iundefsym 424
      nundefsym 45
         tocoff 0
           ntoc 0
      modtaboff 0
        nmodtab 0
   extrefsymoff 0
    nextrefsyms 0
 indirectsymoff 375000
  nindirectsyms 88
      extreloff 0
        nextrel 0
      locreloff 0
        nlocrel 0
Load command 8
     cmd LC_UUID
 cmdsize 24
    uuid C707145F-7276-3E43-A8ED-014C266E0EED
Load command 9
      cmd LC_BUILD_VERSION
  cmdsize 32
 platform 1
    minos 12.0
      sdk 12.1
   ntools 1
     tool 3
  version 711.0
Load command 10
      cmd LC_SOURCE_VERSION
  cmdsize 16
  version 0.0
Load command 11
          cmd LC_LOAD_DYLIB
      cmdsize 56
         name /usr/lib/libSystem.B.dylib (offset 24)
   time stamp 2 Thu Jan  1 01:00:02 1970
      current version 1311.0.0
compatibility version 1.0.0
Load command 12
      cmd LC_FUNCTION_STARTS
  cmdsize 16
  dataoff 366776
 datasize 632
Load command 13
      cmd LC_DATA_IN_CODE
  cmdsize 16
  dataoff 367408
 datasize 88

But currently, I get this in relevant part which makes the shared lib non-relocatable:

Load command 3
          cmd LC_ID_DYLIB
      cmdsize 152
         name /Users/spaceim/.conan/data/openjpeg/2.3.1/_/_/package/bda713dd3b257827c8d11a06ac9d824038871572/lib/libopenjp2.7.dylib (offset 24)
   time stamp 1 Thu Jan  1 01:00:01 1970
      current version 2.3.1
compatibility version 7.0.0

This absolute path should just be @rpath/libopenjp2.7.dylib on macOS.

If openjpeg really wants to hardcode a path in shared lib of the install tree on macOS, at least it would be nice to provide an option to generate relocatable binaries.

But honestly, INSTALL_NAME_DIR shouldn't be hardcoded in a CMakeLists, it should be injected externally with CMAKE_INSTALL_NAME_DIR.