[Runner] Have always host first in CSL paths for LD_LIBRARY_PATH

Having `target` first would make C++ programs for `i686-linux-musl` work, but
then we can't run C++ programs for the host.  We really need to fix the musl
loader.

Author: giordano

src/Runner.jl

@@ -69,12 +69,8 @@ function ld_library_path(target::AbstractPlatform,
     # If requested, start with our CSL libraries for target/host, but only for architectures
     # that can natively run within this environment
     if csl_paths
-        # Ok, this is incredibly finicky.  If the target has the same architecture as the
-        # host, we should have the host first then the target, otherwise we need to have
-        # target first.
-        platforms = arch(target) == arch(host) ? (host, target) : (target, host)
         append!(paths,
-                unique("/usr/lib/csl-$(libc(p))-$(arch(p))" for p in platforms if Sys.islinux(p) && proc_family(p) == "intel"),
+                unique("/usr/lib/csl-$(libc(p))-$(arch(p))" for p in (host, target) if Sys.islinux(p) && proc_family(p) == "intel"),
                 )
     end
 

test/runners.jl

@@ -170,10 +170,15 @@ end
                 ./test
                 """
                 cmd = `/bin/bash -c "$(test_script)"`
-                @test run(ur, cmd, iobuff; tee_stream=devnull)
-                seekstart(iobuff)
-                # Test that we get the output we expect
-                @test endswith(readchomp(iobuff), "Hello World!")
+                if arch(platform) == "i686" && libc(platform) == "musl"
+                    # We can't run this program for this platform
+                    @test_broken run(ur, cmd, iobuff; tee_stream=devnull)
+                else
+                    @test run(ur, cmd, iobuff; tee_stream=devnull)
+                    seekstart(iobuff)
+                    # Test that we get the output we expect
+                    @test endswith(readchomp(iobuff), "Hello World!")
+                end
                 cleanup_dependencies(prefix, artifact_paths, concrete_platform)
             end
         end
@@ -219,10 +224,15 @@ end
                 ./test
                 """
                 cmd = `/bin/bash -c "$(test_script)"`
-                @test run(ur, cmd, iobuff; tee_stream=devnull)
-                seekstart(iobuff)
-                # Test that we get the output we expect
-                @test endswith(readchomp(iobuff), "Hello World!")
+                if arch(platform) == "i686" && libc(platform) == "musl"
+                    # We can't run C++ programs for this platform
+                    @test_broken run(ur, cmd, iobuff; tee_stream=devnull)
+                else
+                    @test run(ur, cmd, iobuff; tee_stream=devnull)
+                    seekstart(iobuff)
+                    # Test that we get the output we expect
+                    @test endswith(readchomp(iobuff), "Hello World!")
+                end
                 cleanup_dependencies(prefix, artifact_paths, concrete_platform)
             end
         end