Man writer: Escape - as \-.

Unescaped -'s become hyphens, while \-'s are left as ascii
minus signs.  That is preferable for use with command-line
options.

See  http://lintian.debian.org/tags/hyphen-used-as-minus-sign.html.
Thanks to Andrea Bolognani for bringing the issue to our
attention.

src/Text/Pandoc/Writers/Man.hs

@@ -105,7 +105,7 @@ manEscapes = [ ('\160', "\\ ")
              , ('\x2014', "\\[em]")
              , ('\x2013', "\\[en]")
              , ('\x2026', "\\&...")
-             ] ++ backslashEscapes "@\\"
+             ] ++ backslashEscapes "-@\\"
 
 -- | Escape special characters for Man.
 escapeString :: String -> String

tests/writer.man

@@ -26,7 +26,7 @@ Here's a regular paragraph.
 In Markdown 1.0.0 and earlier.
 Version 8.
 This line turns into a list item.
-Because a hard-wrapped line in the middle of a paragraph looked like a list
+Because a hard\-wrapped line in the middle of a paragraph looked like a list
 item.
 .PP
 Here's one with a bullet.
@@ -41,7 +41,7 @@ here.
    *   *   *   *   *
 .SH Block Quotes
 .PP
-E-mail style:
+E\-mail style:
 .RS
 .PP
 This is a block quote.
@@ -87,7 +87,7 @@ Code:
 .IP
 .nf
 \f[C]
-----\ (should\ be\ four\ hyphens)
+\-\-\-\-\ (should\ be\ four\ hyphens)
 
 sub\ status\ {
 \ \ \ \ print\ "working";
@@ -489,7 +489,7 @@ Code block:
 .IP
 .nf
 \f[C]
-<!--\ Comment\ -->
+<!\-\-\ Comment\ \-\->
 \f[]
 .fi
 .PP
@@ -568,11 +568,11 @@ Ellipses\&...and\&...and\&....
 .IP \[bu] 2
 223
 .IP \[bu] 2
-\f[I]p\f[]-Tree
+\f[I]p\f[]\-Tree
 .IP \[bu] 2
 Here's some display math:
 .RS
-$\\frac{d}{dx}f(x)=\\lim_{h\\to 0}\\frac{f(x+h)-f(x)}{h}$
+$\\frac{d}{dx}f(x)=\\lim_{h\\to 0}\\frac{f(x+h)\-f(x)}{h}$
 .RE
 .IP \[bu] 2
 Here's one that has a line break in it:
@@ -637,7 +637,7 @@ Left paren: (
 .PP
 Right paren: )
 .PP
-Greater-than: >
+Greater\-than: >
 .PP
 Hash: #
 .PP
@@ -647,7 +647,7 @@ Bang: !
 .PP
 Plus: +
 .PP
-Minus: -
+Minus: \-
 .PP
    *   *   *   *   *
 .SH Links
@@ -718,13 +718,13 @@ In a list?
 .IP \[bu] 2
 It should.
 .PP
-An e-mail address: <nobody@nowhere.net>
+An e\-mail address: <nobody@nowhere.net>
 .RS
 .PP
 Blockquoted: <http://example.com/>
 .RE
 .PP
-Auto-links should not occur here: \f[C]<http://example.com/>\f[]
+Auto\-links should not occur here: \f[C]<http://example.com/>\f[]
 .IP
 .nf
 \f[C]