diff --git a/gas/app.c b/gas/app.c
index dd96b410bad..a3ad146625c 100644
--- a/gas/app.c
+++ b/gas/app.c
@@ -1088,10 +1088,10 @@ do_scrub_chars (size_t (*get) (char *, size_t), char *tostart, size_t tolen)
 	      /* PUT didn't jump out.  We could just break, but we
 		 know what will happen, so optimize a bit.  */
 	      ch = GET ();
-	      old_state = 3;
+	      old_state = 9;
 	    }
-	  else if (state == 9)
-	    old_state = 3;
+	  else if (state == 3)
+	    old_state = 9;
 	  else
 	    old_state = state;
 	  state = 5;
diff --git a/gas/doc/as.texi b/gas/doc/as.texi
index 55b3156f1fa..9a7db3fb81f 100644
--- a/gas/doc/as.texi
+++ b/gas/doc/as.texi
@@ -6186,6 +6186,27 @@ Note: this problem of correctly identifying string parameters to pseudo ops
 also applies to the identifiers used in @code{.irp} (@pxref{Irp})
 and @code{.irpc} (@pxref{Irpc}) as well.
 
+Another issue can occur with the actual arguments passed during macro
+invocation: Multiple arguments can be separated by blanks or commas.  To have
+arguments actually contain blanks or commas (or potentially other non-alpha-
+numeric characters), individual arguments will need to be enclosed in either
+parentheses @code{()}, square brackets @code{[]}, or double quote @code{"}
+characters.  The latter may be the only viable option in certain situations,
+as only double quotes are actually stripped while establishing arguments.  It
+may be important to be aware of two escaping models used when processing such
+quoted argument strings: For one two adjacent double quotes represent a single
+double quote in the resulting argument, going along the lines of the stripping
+of the enclosing quotes.  But then double quotes can also be escaped by a
+backslash @code{\}, but this backslash will not be retained in the resulting
+actual argument as then seen / used while expanding the macro.
+
+As a consequence to the first of these escaping mechanisms two string literals
+intended to be representing separate macro arguments need to be separated by
+white space (or, better yet, by a comma).  To state it differently, such
+adjacent string literals - even if separated only by a blank - will not be
+concatenated when determining macro arguments, even if they're only separated
+by white space.  This is unlike certain other pseudo ops, e.g. @code{.ascii}.
+
 @item .endm
 @cindex @code{endm} directive
 Mark the end of a macro definition.
diff --git a/gas/testsuite/gas/all/gas.exp b/gas/testsuite/gas/all/gas.exp
index a6c64407687..ae7957b2ee0 100644
--- a/gas/testsuite/gas/all/gas.exp
+++ b/gas/testsuite/gas/all/gas.exp
@@ -461,6 +461,8 @@ if [is_elf_format] {
 
 run_dump_test quoted-sym-names
 
+run_list_test macro "-alm"
+
 run_list_test pr20312
 
 load_lib gas-dg.exp
diff --git a/gas/testsuite/gas/all/macro.l b/gas/testsuite/gas/all/macro.l
new file mode 100644
index 00000000000..75fe338f132
--- /dev/null
+++ b/gas/testsuite/gas/all/macro.l
@@ -0,0 +1,25 @@
+# This should match the output of gas -alm macro.s.
+
+.*: Assembler messages:
+.*:10: Error: too many positional arguments
+.*macro.s.*
+
+
+[ 	]*[1-9][0-9]*[ 	]+\.macro[ 	]+m[ 	]+arg1,[ 	]*arg2[ 	]*
+#...
+[ 	]*[1-9][0-9]*[ 	]+\.endm[ 	]*
+[ 	]*[1-9][0-9]*[ 	]+
+[ 	]*[1-9][0-9]*[ 	]+m[ 	]+1,[ 	]*2
+[ 	]*[1-9][0-9]*[ 	]+.... 0+10*[ 	]+>  .byte 1
+[ 	]*[1-9][0-9]*[ 	]+.... 0+20*[ 	]+>  .byte 2
+[ 	]*[1-9][0-9]*[ 	]+m[ 	]+3[ 	]+4
+[ 	]*[1-9][0-9]*[ 	]+.... 0+30*[ 	]+>  .byte 3
+[ 	]*[1-9][0-9]*[ 	]+.... 0+40*[ 	]+>  .byte 4
+[ 	]*[1-9][0-9]*[ 	]+m[ 	]+"5",[ 	]*"6"
+[ 	]*[1-9][0-9]*[ 	]+.... 0+50*[ 	]+>  .byte 5
+[ 	]*[1-9][0-9]*[ 	]+.... 0+60*[ 	]+>  .byte 6
+[ 	]*[1-9][0-9]*[ 	]+m[ 	]+"7"[ 	]+"8"
+[ 	]*[1-9][0-9]*[ 	]+.... 0+70*[ 	]+>  .byte 7
+[ 	]*[1-9][0-9]*[ 	]+.... 0+80*[ 	]+>  .byte 8
+[ 	]*[1-9][0-9]*[ 	]+m[ 	]+""[ 	]+""[ 	]+""
+#pass
diff --git a/gas/testsuite/gas/all/macro.s b/gas/testsuite/gas/all/macro.s
new file mode 100644
index 00000000000..9e70f3067b7
--- /dev/null
+++ b/gas/testsuite/gas/all/macro.s
@@ -0,0 +1,16 @@
+	.macro m arg1, arg2
+	.byte \arg1
+	.byte \arg2
+	.endm
+
+	m 1, 2
+	m 3 4
+	m "5", "6"
+	m "7" "8"
+	m "" "" ""
+
+	.if 0
+	m 1 +2
+	m (3) +4
+	m (5) (6)
+	.endif