feature to mutually exclude extensions?

[CyberLine]

as grpc and protobuf extensions (at least on mac) will not compile due to duplicate symbols, maybe there needs to be an option in ext.json to add extensions, that will not compile with like 'ext-conflicts'

[crazywhalecc]

@CyberLine ext-conflicts was considered earlier, but overriding the validate() method in extension/xxx.php may be a more effective and thorough solution. This method can also be used to determine the minimum compatible PHP version of the extension.

In addition, I have currently tested the combination grpc,protobuf, it can be compiled well on Mac, and there should be no conflict between the two extensions. It would be better if you can provide more information about the environment and compilation commands.

[CyberLine]

Steps to reproduce:

./spc switch-php-version 8.3
./spc download --for-extensions=grpc,protobuf
./spc build --build-cli grpc,protobuf --debug

Build on an M2 Max arm64 Macbook i got those errors:

...
duplicate symbol '__upb_Map_CTypeSizeTable' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Map_Delete' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Arena_SpaceAllocated' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_Array_Move' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '_upb_Arena_IncRefFor' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_MapIterator_Done' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Arena_Init' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_Arena_Fuse' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_Array_Append' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '_upb_Array_Get' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '__upb_Message_DiscardUnknown_shallow' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1045](message.o)
duplicate symbol '_upb_Arena_Free' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_Array_Delete' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '__upb_Map_New' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Message_ExtensionCount' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1045](message.o)
duplicate symbol '_upb_MapIterator_Key' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Arena_DecRefFor' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_Map_Clear' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_MapIterator_Value' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_MapIterator_Next' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Array_Resize' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '_upb_Map_Next' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_kUpb_FltInfinity' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1041](message.o)
duplicate symbol '_kUpb_NaN' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1041](message.o)
duplicate symbol '_upb_Message_New' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1045](message.o)
duplicate symbol '_upb_Message_GetUnknown' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1045](message.o)
duplicate symbol '_upb_Arena_DebugRefCount' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1034](arena.o)
duplicate symbol '_upb_Map_New' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Map_Get' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Map_SetEntryValue' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Array_Set' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '_upb_Map_Insert' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Array_Insert' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '_kUpb_Infinity' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1041](message.o)
duplicate symbol '_upb_Map_Size' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1042](map.o)
duplicate symbol '_upb_Array_New' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1036](array.o)
duplicate symbol '_upb_Message_DeleteUnknown' in:
    /Users/cyberline/Documents/workspace/static-php-cli/source/php-src/ext/protobuf/php-upb.o
    /Users/cyberline/Documents/workspace/static-php-cli/buildroot/lib/libgrpc.a[1045](message.o)
ld: 37 duplicate symbols
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [sapi/cli/php] Error 1