--- a/configure.in
+++ b/configure.in
@@ -1590,16 +1590,17 @@ if test "$GNU_CXX"; then
     # -Wempty-body - catches bugs, e.g. "if (c); foo();", few false positives
     # -Wendif-labels - catches `#else FOO` and `#endif FOO` not in comment
     # -Wint-to-pointer-cast - catches cast to pointer from integer of different size
     # -Wmissing-braces - catches aggregate initializers missing nested braces
     # -Wnon-literal-null-conversion - catches expressions used as a null pointer constant
     # -Woverloaded-virtual - function declaration hides virtual function from base class
     # -Wparentheses - catches `if (a=b)` and operator precedence bugs
     # -Wpointer-arith - catches pointer arithmetic using NULL or sizeof(void)
+    # -Wrange-loop-analysis - catches copies during range-based for loops.
     # -Wreturn-type - catches missing returns, zero false positives
     # -Wsequence-point - catches undefined order behavior like `a = a++`
     # -Wsign-compare - catches comparison of signed and unsigned types
     # -Wswitch - catches switches without all enum cases or default case
     # -Wtrigraphs - catches unlikely use of trigraphs
     # -Wtype-limits - catches overflow bugs, few false positives
     # -Wunused-label - catches unused goto labels
     # -Wwrite-strings - catches non-const char* pointers to string literals
@@ -1621,16 +1622,17 @@ if test "$GNU_CXX"; then
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=sequence-point"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=switch"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=trigraphs"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=type-limits"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=uninitialized"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=unused-label"
 
         MOZ_CXX_SUPPORTS_WARNING(-Werror=, non-literal-null-conversion, ac_cxx_has_werror_non_literal_null_conversion)
+        MOZ_CXX_SUPPORTS_WARNING(-Werror=, range-loop-analysis, ac_cxx_has_range_loop_analysis)
         MOZ_CXX_SUPPORTS_WARNING(-Werror=, sometimes-uninitialized, ac_cxx_has_sometimes_uninitialized)
     fi
 
     # Turn off the following warnings that -Wall turns on:
     # -Wno-invalid-offsetof - we use offsetof on non-POD types frequently
     # -Wno-inline-new-delete - we inline 'new' and 'delete' in mozalloc
     # -Wno-unused-local-typedef - catches unused typedefs, which are commonly used in assertion macros
     #   for performance reasons, and because GCC and clang accept it (though

--- a/js/src/configure.in
+++ b/js/src/configure.in
@@ -1309,16 +1309,17 @@ if test "$GNU_CXX"; then
     # -Wignored-qualifiers - catches returns types with qualifiers like const
     # -Wint-to-pointer-cast - catches cast to pointer from integer of different size
     # -Wmissing-braces - catches aggregate initializers missing nested braces
     # -Wnon-literal-null-conversion - catches expressions used as a null pointer constant
     # -Woverloaded-virtual - function declaration hides virtual function from base class
     # -Wparentheses - catches `if (a=b)` and operator precedence bugs
     # -Wpointer-arith - catches pointer arithmetic using NULL or sizeof(void)
     # -Wpointer-to-int-cast - catches casts from pointer to different sized int
+    # -Wrange-loop-analysis - catches copies during range-based for loops.
     # -Wreorder - catches ctor initializer list not matching class definition order
     # -Wreturn-type - catches missing returns, zero false positives
     # -Wsequence-point - catches undefined order behavior like `a = a++`
     # -Wsign-compare - catches comparison of signed and unsigned types
     # -Wswitch - catches switches without all enum cases or default case
     # -Wtrigraphs - catches unlikely use of trigraphs
     # -Wtype-limits - catches overflow bugs, few false positives
     # -Wunknown-pragmas - catches unexpected #pragma directives
@@ -1349,16 +1350,17 @@ if test "$GNU_CXX"; then
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=uninitialized"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=unknown-pragmas"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=unused-label"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=unused-value"
         _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Werror=write-strings"
 
         MOZ_CXX_SUPPORTS_WARNING(-Werror=, conversion-null, ac_cxx_has_werror_conversion_null)
         MOZ_CXX_SUPPORTS_WARNING(-Werror=, non-literal-null-conversion, ac_cxx_has_werror_non_literal_null_conversion)
+        MOZ_CXX_SUPPORTS_WARNING(-Werror=, range-loop-analysis, ac_cxx_has_range_loop_analysis)
         MOZ_CXX_SUPPORTS_WARNING(-Werror=, sometimes-uninitialized, ac_cxx_has_sometimes_uninitialized)
     fi
 
     # Turn off the following warnings that -Wall turns on:
     # -Wno-invalid-offsetof - we use offsetof on non-POD types frequently
     # -Wno-unused-local-typedef - catches unused typedefs, which are commonly used in assertion macros
     #
     _WARNINGS_CXXFLAGS="${_WARNINGS_CXXFLAGS} -Wno-invalid-offsetof"