dev-lang/rust: colliding debug information in /usr/lib/debug/.build-id - slot conflict

[stsydow]

There is a slot conflict for dev-lang/rust.
dev-lang/rust-1.13.0 and dev-lang/rust-99 (1.14.0)
have colliding debug information files in /usr/lib/debug/.build-id/:

 * Messages for package dev-lang/rust-1.13.0:

 * This package will overwrite one or more files that may belong to other
 * packages (see list below).
 * 
 * Detected file collision(s):
 * 
 * 	/usr/lib/debug/.build-id/12/7da749021c1fc1a58cba734a1f542cbe2b7ce4
 * 	/usr/lib/debug/.build-id/12/7da749021c1fc1a58cba734a1f542cbe2b7ce4.debug
 * 	/usr/lib/debug/.build-id/7a/ac4ce39f67b9445d4467601026804a66a85875
 * 	/usr/lib/debug/.build-id/7a/ac4ce39f67b9445d4467601026804a66a85875.debug
 * 	/usr/lib/debug/.build-id/1a/9659e10c985a24645276bcf58daa177a335ba7
 * 	/usr/lib/debug/.build-id/1a/9659e10c985a24645276bcf58daa177a335ba7.debug
 * 	/usr/lib/debug/.build-id/97/091ea97fd941c053322a306489efd39bd23d45
 * 	/usr/lib/debug/.build-id/97/091ea97fd941c053322a306489efd39bd23d45.debug
 * 	/usr/lib/debug/.build-id/ec/f403d44937761be3d2fa33840b4a5703f92160
 * 	/usr/lib/debug/.build-id/ec/f403d44937761be3d2fa33840b4a5703f92160.debug
 * 	/usr/lib/debug/.build-id/fb/8f0115c78a00f18711f375cdee0d72cb3afc3a
 * 	/usr/lib/debug/.build-id/fb/8f0115c78a00f18711f375cdee0d72cb3afc3a.debug
 * 	/usr/lib/debug/.build-id/3a/edf04b4e4339ab77a3bbc7f12d434790b0a3f5
 * 	/usr/lib/debug/.build-id/3a/edf04b4e4339ab77a3bbc7f12d434790b0a3f5.debug
 * 	/usr/lib/debug/.build-id/8e/706726737a90dfda50f88c9effe7b8e1e9821a
 * 	/usr/lib/debug/.build-id/8e/706726737a90dfda50f88c9effe7b8e1e9821a.debug
 * 	/usr/lib/debug/.build-id/93/376cbe94ccc774d4c3e8586de7a574065214fe
 * 	/usr/lib/debug/.build-id/93/376cbe94ccc774d4c3e8586de7a574065214fe.debug
 * 	/usr/lib/debug/.build-id/49/4b8c07c75ea08c8de6d94f5245c17d94247b5b
 * 	/usr/lib/debug/.build-id/49/4b8c07c75ea08c8de6d94f5245c17d94247b5b.debug
 * 	/usr/lib/debug/.build-id/a1/53fcfe0dc0c17b645c17580f798c8dd41981f7
 * 	/usr/lib/debug/.build-id/a1/53fcfe0dc0c17b645c17580f798c8dd41981f7.debug
 * 	/usr/lib/debug/.build-id/7b/8bc3685c3e04fb9fa342793ab593166a9ab6e3
 * 	/usr/lib/debug/.build-id/7b/8bc3685c3e04fb9fa342793ab593166a9ab6e3.debug
 * 	/usr/lib/debug/.build-id/7e/7c8a2a700e6eacc0dfc3b3bef1581318e42ab1
 * 	/usr/lib/debug/.build-id/7e/7c8a2a700e6eacc0dfc3b3bef1581318e42ab1.debug
 * 	/usr/lib/debug/.build-id/09/08d5313c84a73352903724405ed7cae82097cf
 * 	/usr/lib/debug/.build-id/09/08d5313c84a73352903724405ed7cae82097cf.debug
 * 	/usr/lib/debug/.build-id/bb/b4320ee34bd200ac02580b08a17570d1c57f09
 * 	/usr/lib/debug/.build-id/bb/b4320ee34bd200ac02580b08a17570d1c57f09.debug
 * 	/usr/lib/debug/.build-id/b3/322f0967562fab8e7b7ea9862c7b3769776573
 * 	/usr/lib/debug/.build-id/b3/322f0967562fab8e7b7ea9862c7b3769776573.debug
 * 	/usr/lib/debug/.build-id/2f/2e3a48ea6ec7f317e8d07066fba2cc3fa45063
 * 	/usr/lib/debug/.build-id/2f/2e3a48ea6ec7f317e8d07066fba2cc3fa45063.debug
 * 	/usr/lib/debug/.build-id/84/9ae2cb2b2ca10ee6a6616ca53b68f50753698b
 * 	/usr/lib/debug/.build-id/84/9ae2cb2b2ca10ee6a6616ca53b68f50753698b.debug
 * 	/usr/lib/debug/.build-id/38/a9f4d13bb7c3fe1153ed031c1e1a0ae6800842
 * 	/usr/lib/debug/.build-id/38/a9f4d13bb7c3fe1153ed031c1e1a0ae6800842.debug
 * 	/usr/lib/debug/.build-id/36/76b0c8f0930b305e2f7f9cd8c31dc07bde9ca0
 * 	/usr/lib/debug/.build-id/36/76b0c8f0930b305e2f7f9cd8c31dc07bde9ca0.debug
 * 	/usr/lib/debug/.build-id/10/083b9011ad09d9b6ee83abcc2df4fca3b486ff
 * 	/usr/lib/debug/.build-id/10/083b9011ad09d9b6ee83abcc2df4fca3b486ff.debug
 * 	/usr/lib/debug/.build-id/33/059907b1a8c998e80c972f4ca61caff79f7448
 * 	/usr/lib/debug/.build-id/33/059907b1a8c998e80c972f4ca61caff79f7448.debug
 * 	/usr/lib/debug/.build-id/bf/c2af7635ff89fc69c0de11af2c27304d9d1903
 * 	/usr/lib/debug/.build-id/bf/c2af7635ff89fc69c0de11af2c27304d9d1903.debug
 * 	/usr/lib/debug/.build-id/d0/68d3c08476cad2387d4a67ab4f205713c00dcd
 * 	/usr/lib/debug/.build-id/d0/68d3c08476cad2387d4a67ab4f205713c00dcd.debug
 * 	/usr/lib/debug/.build-id/47/b47e0960048e96bd68fff9db72e8ef97931439
 * 	/usr/lib/debug/.build-id/47/b47e0960048e96bd68fff9db72e8ef97931439.debug
 * 	/usr/lib/debug/.build-id/b6/9a07ac1df04254a7cf5fe6043710c7a9ff695c
 * 	/usr/lib/debug/.build-id/b6/9a07ac1df04254a7cf5fe6043710c7a9ff695c.debug
 * 
 * Searching all installed packages for file collisions...
 * 
 * Press Ctrl-C to Stop
 * 
 * dev-lang/rust-99:beta::rust
 * 	/usr/lib/debug/.build-id/12/7da749021c1fc1a58cba734a1f542cbe2b7ce4
 * 	/usr/lib/debug/.build-id/12/7da749021c1fc1a58cba734a1f542cbe2b7ce4.debug
 * 	/usr/lib/debug/.build-id/1a/9659e10c985a24645276bcf58daa177a335ba7
 * 	/usr/lib/debug/.build-id/1a/9659e10c985a24645276bcf58daa177a335ba7.debug
 * 	/usr/lib/debug/.build-id/3a/edf04b4e4339ab77a3bbc7f12d434790b0a3f5
 * 	/usr/lib/debug/.build-id/3a/edf04b4e4339ab77a3bbc7f12d434790b0a3f5.debug
 * 	/usr/lib/debug/.build-id/49/4b8c07c75ea08c8de6d94f5245c17d94247b5b
 * 	/usr/lib/debug/.build-id/49/4b8c07c75ea08c8de6d94f5245c17d94247b5b.debug
 * 	/usr/lib/debug/.build-id/7a/ac4ce39f67b9445d4467601026804a66a85875
 * 	/usr/lib/debug/.build-id/7a/ac4ce39f67b9445d4467601026804a66a85875.debug
 * 	/usr/lib/debug/.build-id/8e/706726737a90dfda50f88c9effe7b8e1e9821a
 * 	/usr/lib/debug/.build-id/8e/706726737a90dfda50f88c9effe7b8e1e9821a.debug
 * 	/usr/lib/debug/.build-id/93/376cbe94ccc774d4c3e8586de7a574065214fe
 * 	/usr/lib/debug/.build-id/93/376cbe94ccc774d4c3e8586de7a574065214fe.debug
 * 	/usr/lib/debug/.build-id/97/091ea97fd941c053322a306489efd39bd23d45
 * 	/usr/lib/debug/.build-id/97/091ea97fd941c053322a306489efd39bd23d45.debug
 * 	/usr/lib/debug/.build-id/ec/f403d44937761be3d2fa33840b4a5703f92160
 * 	/usr/lib/debug/.build-id/ec/f403d44937761be3d2fa33840b4a5703f92160.debug
 * 	/usr/lib/debug/.build-id/fb/8f0115c78a00f18711f375cdee0d72cb3afc3a
 * 	/usr/lib/debug/.build-id/fb/8f0115c78a00f18711f375cdee0d72cb3afc3a.debug
 * 
 * Package 'dev-lang/rust-1.13.0' NOT merged due to file collisions. If
 * necessary, refer to your elog messages for the whole content of the
 * above message.
 * 
 * The following package has failed to build, install, or execute postinst:
 * 
 *  (dev-lang/rust-1.13.0:stable/1.13::rust, ebuild scheduled for merge), Log file:
 *   '/var/tmp/portage/dev-lang/rust-1.13.0/temp/build.log'
 * 

[cnd]

honestly I didn't expected their parallel installation