If a tbl(7) layout contains unknown font modifiers, fall back to the

default font rather than failing the whole table.
Needed by some pages in books/man-pages-posix.
Written on the plane back from EuroBSDCon in Sofia.

2 files changed, 12 insertions, 2 deletions

diff --git a/mandoc.1 b/mandoc.1
index 593ff91d..1cb4d93c 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -1134,11 +1134,16 @@ or
 The invalid argument is moved out of the macro, which leaves the macro
 empty, causing it to toggle the spacing mode.
 .It Sy "unknown font, skipping request"
-.Pq man
+.Pq man , tbl
 A
 .Xr roff 7
 .Ic \&ft
-request has an invalid argument.
+request or a
+.Xr tbl 7
+.Ic \&f
+layout modifier has an unknown
+.Ar font
+argument.
 .El
 .Ss "Warnings related to plain text"
 .Bl -ohang
diff --git a/tbl_layout.c b/tbl_layout.c
index b0e0ae98..b78e8881 100644
--- a/tbl_layout.c
+++ b/tbl_layout.c
@@ -201,6 +201,11 @@ mod:
 	default:
 		break;
 	}
+	if (isalnum((unsigned char)p[*pos - 1])) {
+		mandoc_vmsg(MANDOCERR_FT_BAD, tbl->parse,
+		    ln, *pos - 1, "TS f%c", p[*pos - 1]);
+		goto mod;
+	}
 
 	mandoc_msg(MANDOCERR_TBLLAYOUT, tbl->parse,
 	    ln, *pos - 1, NULL);