travis: install llvm-* to get llvm-symbolizer

Backtraces like
```
misc-utils/cal.c:295:4: runtime error: signed integer overflow: 2147483647 + 5 cannot be represented in type 'int'
==1405==WARNING: invalid path to external symbolizer!
==1405==WARNING: Failed to use and restart external symbolizer!
    #0 0x4c4c09  (/home/travis/build/karelzak/util-linux/cal+0x4c4c09)
    #1 0x7f4363046b96  (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #2 0x41bab9  (/home/travis/build/karelzak/util-linux/cal+0x41bab9)
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior misc-utils/cal.c:295:4 in
```
aren't very helpful

It's follow-up to https://github.com/karelzak/util-linux/pull/1075

diff --git a/.travis-functions.sh b/.travis-functions.sh
index 3a2e00018bb350f8518af17c1f90f0f6ecbd96c5..b11d9ef60baef9d33914c938820d392ae9550630 100755 (executable)
--- a/.travis-functions.sh
+++ b/.travis-functions.sh
@@ -142,7 +142,7 @@ function travis_install_script
                # the following snippet was borrowed from https://apt.llvm.org/llvm.sh
                wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
                sudo add-apt-repository -y "deb http://apt.llvm.org/$ubuntu_release/   llvm-toolchain-$ubuntu_release-$clang_version  main"
-               additional_packages+=(clang-$clang_version)
+               additional_packages+=(clang-$clang_version llvm-$clang_version)
        elif [[ "$CC" =~ ^gcc-([0-9]+)$ ]]; then
                gcc_version=${BASH_REMATCH[1]}
                sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test