diff --git a/llvm/test/tools/llvm-symbolizer/output-style-inlined.test b/llvm/test/tools/llvm-symbolizer/output-style-inlined.test
--- a/llvm/test/tools/llvm-symbolizer/output-style-inlined.test
+++ b/llvm/test/tools/llvm-symbolizer/output-style-inlined.test
@@ -6,6 +6,10 @@
 
 RUN: llvm-symbolizer --no-inlines -e %p/Inputs/addr.exe 0x40054d \
 RUN:   | FileCheck %s --check-prefix=LLVM --implicit-check-not=inctwo
+## Before 2020-08-04, asan_symbolize.py passed --inlining=false if 'symbolize_inline_frames'
+## is set to false. Support this compatibility alias for a while.
+RUN: llvm-symbolizer --inlining=false -e %p/Inputs/addr.exe 0x40054d \
+RUN:   | FileCheck %s --check-prefix=LLVM --implicit-check-not=inctwo
 
 RUN: llvm-symbolizer --output-style=LLVM --no-inlines -e %p/Inputs/addr.exe 0x40054d \
 RUN:   | FileCheck %s --check-prefix=LLVM --implicit-check-not=inctwo
diff --git a/llvm/test/tools/llvm-symbolizer/sym.test b/llvm/test/tools/llvm-symbolizer/sym.test
--- a/llvm/test/tools/llvm-symbolizer/sym.test
+++ b/llvm/test/tools/llvm-symbolizer/sym.test
@@ -26,6 +26,10 @@
 RUN: llvm-symbolizer -inlines -print-address -p -obj=%p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck -check-prefix="PRETTY" %s
 RUN: llvm-symbolizer -i -print-address -pretty-print -obj=%p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck -check-prefix="PRETTY" %s
 RUN: llvm-symbolizer -i -print-address -p -obj=%p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck -check-prefix="PRETTY" %s
+## Before 2020-08-04, asan_symbolize.py passed --inlining=true.
+## Support this compatibility alias for a while.
+RUN: llvm-symbolizer --inlining=true --print-address -p --obj=%p/Inputs/addr.exe < %p/Inputs/addr.inp | FileCheck -check-prefix="PRETTY" %s
+
 RUN: echo "0x1" > %t.input
 RUN: llvm-symbolizer -obj=%p/Inputs/zero < %t.input | FileCheck -check-prefix="ZERO" %s
 
diff --git a/llvm/tools/llvm-symbolizer/Opts.td b/llvm/tools/llvm-symbolizer/Opts.td
--- a/llvm/tools/llvm-symbolizer/Opts.td
+++ b/llvm/tools/llvm-symbolizer/Opts.td
@@ -58,3 +58,7 @@
 def : F<"inlining", "Alias for --inlines">, Alias<inlines>;
 def : Flag<["-"], "p">, Alias<pretty_print>, HelpText<"Alias for --pretty-print">;
 def : Flag<["-"], "s">, Alias<basenames>, HelpText<"Alias for --basenames">;
+
+// Compatibility aliases for old asan_symbolize.py and sanitizer binaries (before 2020-08).
+def : Flag<["--"], "inlining=true">, Alias<inlines>, HelpText<"Alias for --inlines">;
+def : Flag<["--"], "inlining=false">, Alias<no_inlines>, HelpText<"Alias for --no-inlines">;