diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_file.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_file.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_file.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_file.cpp
@@ -58,6 +58,9 @@
   } else {
     internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
   }
+  if (common_flags()->log_suffix) {
+    internal_strlcat(full_path, common_flags()->log_suffix, kMaxPathLength);
+  }
   error_t err;
   fd = OpenFile(full_path, WrOnly, &err);
   if (fd == kInvalidFd) {
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc b/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc
--- a/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc
@@ -59,6 +59,8 @@
     bool, log_exe_name, false,
     "Mention name of executable when reporting error and "
     "append executable name to logs (as in \"log_path.exe_name.pid\").")
+COMMON_FLAG(const char *, log_suffix, nullptr,
+            "String to append to log file name, e.g. \".txt\".")
 COMMON_FLAG(
     bool, log_to_syslog, (bool)SANITIZER_ANDROID || (bool)SANITIZER_MAC,
     "Write all sanitizer output to syslog in addition to other means of "
diff --git a/compiler-rt/test/sanitizer_common/TestCases/suffix-log-path_test.c b/compiler-rt/test/sanitizer_common/TestCases/suffix-log-path_test.c
new file mode 100644
--- /dev/null
+++ b/compiler-rt/test/sanitizer_common/TestCases/suffix-log-path_test.c
@@ -0,0 +1,22 @@
+// RUN: %clang %s -o %T/suffix-log-path_test-binary
+
+// The glob below requires bash.
+// REQUIRES: shell
+
+// Good log_path with suffix.
+// RUN: rm -f %T/sanitizer.log.*.txt
+// RUN: %env_tool_opts=log_path=%T/sanitizer.log:log_exe_name=1:log_suffix=.txt %run %T/suffix-log-path_test-binary 2> %t.out
+// RUN: FileCheck %s < %T/sanitizer.log.suffix-log-path_test-binary.*.txt
+
+// UNSUPPORTED: ios, android
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <sanitizer/common_interface_defs.h>
+
+int main(int argc, char **argv) {
+  __sanitizer_print_stack_trace();
+  return 0;
+}
+// CHECK: #{{.*}} main