xmobar also needs libm (due to libiw) :(

iwlib-0.1.0-libm.patch

@@ -1,10 +1,21 @@
---- iwlib-0.1.0/iwlib.cabal~	2018-01-31 07:00:13.000000000 +0800
-+++ iwlib-0.1.0/iwlib.cabal	2019-03-04 11:24:19.033283194 +0800
+--- xmobar-0.29.4/iwlib-0.1.0/iwlib.cabal~	2018-01-31 07:00:13.000000000 +0800
++++ xmobar-0.29.4/iwlib-0.1.0/iwlib.cabal	2019-03-04 11:24:19.033283194 +0800
 @@ -24,5 +24,5 @@
    includes:            iwlib.h
    default-language:    Haskell2010
    exposed-modules:     Network.IWlib
 -  extra-libraries:     iw
-+  extra-libraries:     iw, m
++  extra-libraries:     iw m
    ghc-options:         -Wall
 \ No newline at end of file
+--- xmobar-0.29.4/xmobar.cabal~	2019-03-04 11:32:13.826170026 +0800
++++ xmobar-0.29.4/xmobar.cabal	2019-03-04 11:48:38.178168287 +0800
+@@ -157,7 +157,7 @@
+                    Xmobar.Plugins.Monitors.Bright,
+                    Xmobar.Plugins.Monitors.CatInt
+ 
+-    extra-libraries: Xrandr Xrender
++    extra-libraries: Xrandr Xrender m
+ 
+     ghc-options: -funbox-strict-fields -Wall -fno-warn-unused-do-bind
+ 

xmobar.spec

@@ -111,7 +111,7 @@ This package provides the Haskell %{name} library development files.
 %setup -q -a1
 # End cabal-rpm setup
 %patch0 -p1 -b .orig
-%patch1 -p0 -b .orig
+%patch1 -p1 -b .orig
 
 
 %build