diff --git a/gdb/testsuite/gdb.base/libsegfault.exp b/gdb/testsuite/gdb.base/libsegfault.exp
index 2c16fe8932a..fb62bdb8746 100644
--- a/gdb/testsuite/gdb.base/libsegfault.exp
+++ b/gdb/testsuite/gdb.base/libsegfault.exp
@@ -42,7 +42,7 @@ proc gdb_spawn_with_ld_preload {lib cmdline_opts} {
 	# ASan runtime does not come first in initial library list; you should
 	# either link runtime to your application or manually preload it with
 	# LD_PRELOAD.
-	set_sanitizer_default ASAN_OPTIONS verify_asan_link_order 0
+	append_environment ASAN_OPTIONS verify_asan_link_order 0
 
 	gdb_spawn_with_cmdline_opts $cmdline_opts
     }
diff --git a/gdb/testsuite/gdb.threads/attach-slow-waitpid.exp b/gdb/testsuite/gdb.threads/attach-slow-waitpid.exp
index 28d70daad8c..abe8d434558 100644
--- a/gdb/testsuite/gdb.threads/attach-slow-waitpid.exp
+++ b/gdb/testsuite/gdb.threads/attach-slow-waitpid.exp
@@ -83,7 +83,7 @@ proc gdb_spawn_with_ld_preload {lib} {
 	# ASan runtime does not come first in initial library list; you should
 	# either link runtime to your application or manually preload it with
 	# LD_PRELOAD.
-	set_sanitizer_default ASAN_OPTIONS verify_asan_link_order 0
+	append_environment ASAN_OPTIONS verify_asan_link_order 0
 
 	gdb_start
     }
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 7ee2043f0f8..a86f534528c 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -76,11 +76,11 @@ proc set_sanitizer { env_var var_id val } {
 
 # Add VAR_ID=VAL to ENV_VAR, unless ENV_VAR already contains a VAR_ID setting.
 
-proc set_sanitizer_default { env_var var_id val } {
+proc append_environment { env_var var_id val } {
     set_sanitizer_1 $env_var $var_id $val 1
 }
 
-set_sanitizer_default TSAN_OPTIONS suppressions \
+append_environment TSAN_OPTIONS suppressions \
     $srcdir/../tsan-suppressions.txt
 
 # When using ThreadSanitizer we may run into the case that a race is detected,
@@ -89,14 +89,14 @@ set_sanitizer_default TSAN_OPTIONS suppressions \
 # Try to prevent this by setting history_size to the maximum (7) by default.
 # See also the ThreadSanitizer docs (
 # https://github.com/google/sanitizers/wiki/ThreadSanitizerFlags ).
-set_sanitizer_default TSAN_OPTIONS history_size 7
+append_environment TSAN_OPTIONS history_size 7
 
 # If GDB is built with ASAN (and because there are leaks), it will output a
 # leak report when exiting as well as exit with a non-zero (failure) status.
 # This can affect tests that are sensitive to what GDB prints on stderr or its
 # exit status.  Add `detect_leaks=0` to the ASAN_OPTIONS environment variable
 # (which will affect any spawned sub-process) to avoid this.
-set_sanitizer_default ASAN_OPTIONS detect_leaks 0
+append_environment ASAN_OPTIONS detect_leaks 0
 
 # List of procs to run in gdb_finish.
 set gdb_finish_hooks [list]