tcwg_gnu-build.sh: Clean sysroot when re-building linux headers or glibc

Change-Id: I6a3b8ba5552fb82762d7ef72a4d3202dd37ffc8a

1 files changed, 20 insertions, 0 deletions

diff --git a/round-robin.sh b/round-robin.sh
index 60e28cf1..de33c873 100644
--- a/round-robin.sh
+++ b/round-robin.sh
@@ -447,6 +447,26 @@ build_abe ()
     )
 }
 
+# If we bisect a regression between different major versions of Glibc,
+# then we might get a mixed sysroot with several versions of ld-M.N.so and
+# other binaries installed side-by-side.  Such a sysroot will break
+# benchmarking, which requires a single ld-*.so binary to be present.
+# Similarly, weird problems can occur if we are bisecting linux
+# and re-installing kernel headers one on top another.
+# Forcefully delete sysroot before building C library or linux headers.
+clean_sysroot ()
+{
+    (
+    set -euf -o pipefail
+
+    local gnu_target sysroot
+    gnu_target=$(print_gnu_target ${rr[target]})
+    sysroot="$(pwd)/abe/builds/destdir/x86_64-pc-linux-gnu/$gnu_target/libc"
+
+    rm -rf "$sysroot"
+    )
+}
+
 # Build LLVM
 build_llvm ()
 {