So I have a NeoVim setup I made a long time ago. A friend convinced me that the Solarized terminal theme was awesome and so I have that configured, not sure if I have a matching Vim theme.
Anyhow, when I started using Rust and C++, the compiler warnings were highlighted in the same color as the text. This was mostly for unused imports and the like, so I didn't bother much. However recently it got very much in my way when looking at C code.
This is the situation:

(The line reads use std::io;, but the font color matches the highlight.)
So my question is if anyone knows how to edit the highlight color? I don't remember where I setup the theme, I think it might be in ~/.Xresources:
Xft.dpi: 104
Xft.antialias: true
Xft.hinting: true
Xft.rgba: rgb
Xft.hintstyle: hintfull Xcursor.size: 40
URxvt.termName: xterm-256color
URxvt.font: xft:DejaVu Sans Mono:pixelsize=24
URxvt.scrollBar: false
URxvt.scrollStyle: rxvt
URxvt.internalBorder: 20
URxvt.letterSpace: -2
URxvt.iso14755: False
URxvt.iso14755_52: False
#define S_base03 #002b36
#define S_base02 #073642
#define S_base01 #586e75
#define S_base00 #657b83
#define S_base0 #839496
#define S_base1 #93a1a1
#define S_base2 #eee8d5
#define S_base3 #fdf6e3
*background: S_base03
*foreground: S_base0
*fadeColor: S_base03
*cursorColor: S_base1
*pointerColorBackground:S_base01
*pointerColorForeground:S_base1
#define S_yellow #b58900
#define S_orange #cb4b16
#define S_red #dc322f
#define S_magenta #d33682
#define S_violet #6c71c4
#define S_blue #268bd2
#define S_cyan #2aa198
#define S_green #859900
!! black dark/light
*color0: S_base02
*color8: S_base03
!! red dark/light
*color1: S_red
*color9: S_orange
!! green dark/light
*color2: S_green
*color10: S_base01
!! yellow dark/light
*color3: S_yellow
*color11: S_base00
!! blue dark/light
*color4: S_blue
*color12: S_base0
!! magenta dark/light
*color5: S_magenta
*color13: S_violet
!! cyan dark/light
*color6: S_cyan
*color14: S_base1
!! white dark/light
*color7: S_base2
*color15: S_base3