[Tex/LaTex] How te get bold + small caps with latin modern or computer modern

Question

I'm trying to use xeLaTeX …
But I dont' get bold smallcap fonts with the standard font (latin modern or computer modern ?).

With LaTeX, I used this to solve the probleme because I know that bold smallcaps doesnt' exit with lmodern.

   \usepackage{lmodern} \usepackage{fix-cm}
   \rmfamily
   \DeclareFontShape{T1}{lmr}{b}{sc}{<->ssub*cmr/bx/sc}{}
   \DeclareFontShape{T1}{lmr}{bx}{sc}{<->ssub*cmr/bx/sc}{}

How to make something like this with xeLaTeX ?
Perhaps using cm-unicode (for the missing fonts) ? But I don't understand how to do that …

I've seen more post about this problem, but no solution was given.

Thank you.

\documentclass[a4paper,10pt]{article}
\usepackage{fontspec}
\usepackage{xunicode}

\begin{document}

\textsc{\textbf{Essai 1}}

\textbf{\textsc{Essai 2}}

{\fontseries{b}\fontshape{sc}\selectfont Essai 3}

{\fontseries{bx}\fontshape{sc}\selectfont Essai 3}

\end{document}

I already tried to use \setmainfont{CMU Serif} but I get an error :

! The font "CMU Serif" cannot be found.

\documentclass[11pt]{article}

    \usepackage[tuenc]{fontspec}%for lualatex case

\setmainfont{CMU Serif}

\begin{document}

  not bold or caps

\textsc{small caps}    

\textbf{\textsc{bold small caps}}

\textbf{bold}

\end{document} 

And the log :

This is XeTeX, Version 3.14159265-2.6-0.99996 (TeX Live 2016) (preloaded format=xelatex 2016.8.4)  16 OCT 2016 19:51
entering extended mode
 restricted \write18 enabled.
 %&-line parsing enabled.
**ECM_solution.tex
(./ECM_solution.tex
LaTeX2e <2016/03/31> patch level 3
Babel <3.9r> and hyphenation patterns for 83 language(s) loaded.
(/usr/local/texlive/2016/texmf-dist/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/local/texlive/2016/texmf-dist/tex/latex/base/size11.clo
File: size11.clo 2014/09/29 v1.4h Standard LaTeX file (size option)
)
\c@part=\count79
\c@section=\count80
\c@subsection=\count81
\c@subsubsection=\count82
\c@paragraph=\count83
\c@subparagraph=\count84
\c@figure=\count85
\c@table=\count86
\abovecaptionskip=\skip41
\belowcaptionskip=\skip42
\bibindent=\dimen102
)
(/usr/local/texlive/2016/texmf-dist/tex/latex/fontspec/fontspec.sty
(/usr/local/texlive/2016/texmf-dist/tex/latex/l3kernel/expl3.sty
Package: expl3 2016/05/18 v6512 L3 programming layer (loader) 

(/usr/local/texlive/2016/texmf-dist/tex/latex/l3kernel/expl3-code.tex
Package: expl3 2016/05/18 v6512 L3 programming layer (code)
L3 Module: l3bootstrap 2016/02/12 v6412 L3 Bootstrap code
L3 Module: l3names 2016/03/11 v6433 L3 Namespace for primitives
L3 Module: l3basics 2015/11/22 v6315 L3 Basic definitions
L3 Module: l3expan 2015/09/10 v5983 L3 Argument expansion
L3 Module: l3tl 2016/03/26 v6465 L3 Token lists
L3 Module: l3str 2016/03/24 v6441 L3 Strings
L3 Module: l3seq 2015/08/05 v5777 L3 Sequences and stacks
L3 Module: l3int 2016/03/24 v6441 L3 Integers
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L3 Module: l3quark 2015/08/17 v5855 L3 Quarks
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L3 Module: l3token 2016/04/03 v6470 L3 Experimental token manipulation
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L3 Module: l3msg 2016/03/26 v6464 L3 Messages
L3 Module: l3file 2016/03/25 v6458 L3 File and I/O operations
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\l__iow_current_line_int=\count95
\l__iow_current_word_int=\count96
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L3 Module: l3skip 2016/01/05 v6366 L3 Dimensions and skips
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\g_tmpa_dim=\dimen107
\g_tmpb_dim=\dimen108
\c_zero_skip=\skip43
\c_max_skip=\skip44
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\g_tmpa_skip=\skip47
\g_tmpb_skip=\skip48
\c_zero_muskip=\muskip10
\c_max_muskip=\muskip11
\l_tmpa_muskip=\muskip12
\l_tmpb_muskip=\muskip13
\g_tmpa_muskip=\muskip14
\g_tmpb_muskip=\muskip15
L3 Module: l3keys 2015/11/17 v6284 L3 Key-value interfaces
\g__keyval_level_int=\count98
\l_keys_choice_int=\count99
L3 Module: l3fp 2016/03/26 v6465 L3 Floating points
\c__fp_leading_shift_int=\count100
\c__fp_middle_shift_int=\count101
\c__fp_trailing_shift_int=\count102
\c__fp_big_leading_shift_int=\count103
\c__fp_big_middle_shift_int=\count104
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\c__fp_Bigg_leading_shift_int=\count106
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\c__fp_Bigg_trailing_shift_int=\count108
L3 Module: l3box 2015/08/09 v5822 L3 Experimental boxes
\c_empty_box=\box26
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\g_tmpa_box=\box29
\g_tmpb_box=\box30
L3 Module: l3coffins 2016/05/17 v6508 L3 Coffin code layer
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\l__coffin_display_coffin=\box37
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\l__coffin_display_offset_dim=\dimen116
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L3 Module: l3color 2014/08/23 v5354 L3 Experimental color support
L3 Module: l3sys 2015/09/25 v6087 L3 Experimental system/runtime functions
L3 Module: l3candidates 2016/05/13 v6484 L3 Experimental additions to l3kernel
\l__box_top_dim=\dimen119
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\l__box_top_new_dim=\dimen123
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\l__box_internal_box=\box40
\l__coffin_bounding_shift_dim=\dimen127
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\l__coffin_right_corner_dim=\dimen129
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\l__coffin_top_corner_dim=\dimen131
\l__coffin_scaled_total_height_dim=\dimen132
\l__coffin_scaled_width_dim=\dimen133
L3 Module: l3luatex 2016/03/26 v6465 L3 Experimental LuaTeX-specific functions
)
(/usr/local/texlive/2016/texmf-dist/tex/latex/l3kernel/l3xdvipdfmx.def
File: l3xdvidpfmx.def 2016/03/26 v6465 L3 Experimental driver: xdvipdfmx
\l__driver_tmp_box=\box41
))
(/usr/local/texlive/2016/texmf-dist/tex/latex/l3packages/xparse/xparse.sty
Package: xparse 2016/05/18 v6512 L3 Experimental document command parser
\l__xparse_current_arg_int=\count109
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\l__xparse_mandatory_args_int=\count111
\l__xparse_processor_int=\count112
\l__xparse_v_nesting_int=\count113
)
Package: fontspec 2016/02/01 v2.5a Font selection for XeLaTeX and LuaLaTeX

(/usr/local/texlive/2016/texmf-dist/tex/latex/fontspec/fontspec-xetex.sty
Package: fontspec-xetex 2016/02/01 v2.5a Font selection for XeLaTeX and LuaLaTe
X
\l_fontspec_script_int=\count114
\l_fontspec_language_int=\count115
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\l__fontspec_tmpa_dim=\dimen134
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\l__fontspec_tmpc_dim=\dimen136
\g__file_internal_ior=\read1

(/usr/local/texlive/2016/texmf-dist/tex/latex/base/fontenc.sty
Package: fontenc 2016/06/19 v1.99m Standard LaTeX package

(/usr/local/texlive/2016/texmf-dist/tex/latex/fontspec/tuenc.def
File: tuenc.def 2016/01/29 v0.1 Unicode font encoding for LaTeX2e

(/usr/local/texlive/2016/texmf-dist/tex/latex/fontspec/tufontrange-T1.def
File: ucfontrange-T1.def 
)
(/usr/local/texlive/2016/texmf-dist/tex/latex/fontspec/tufontrange-TS1.def
File: ucfontrange-TS1.def 
)))
.................................................
. LaTeX info: "xparse/define-command"
. 
. Defining command \__fontspec_post_arg:w with sig. 'mmO{}' on line 353.
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. LaTeX info: "xparse/define-command"
. 
. Defining command \fontspec with sig. 'om' on line 355.
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. LaTeX info: "xparse/define-command"
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. Defining command \setmainfont with sig. 'om' on line 365.
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. LaTeX info: "xparse/define-command"
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. Defining command \setsansfont with sig. 'om' on line 375.
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. LaTeX info: "xparse/define-command"
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. Defining command \setmonofont with sig. 'om' on line 385.
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. LaTeX info: "xparse/define-command"
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. Defining command \setmathrm with sig. 'om' on line 399.
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. LaTeX info: "xparse/define-command"
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. Defining command \setboldmathrm with sig. 'om' on line 407.
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. LaTeX info: "xparse/define-command"
. 
. Defining command \setmathsf with sig. 'om' on line 415.
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. LaTeX info: "xparse/define-command"
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. Defining command \setmathtt with sig. 'om' on line 423.
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. LaTeX info: "xparse/define-command"
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. Defining command \newfontfamily with sig. 'mom' on line 437.
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. Defining command \newfontface with sig. 'mom' on line 453.
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. LaTeX info: "xparse/define-command"
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. Defining command \defaultfontfeatures with sig. 't+om' on line 467.
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. LaTeX info: "xparse/define-command"
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. Defining command \addfontfeatures with sig. 'm' on line 529.
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. Defining command \newfontfeature with sig. 'mm' on line 540.
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. LaTeX info: "xparse/define-command"
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. Defining command \newAATfeature with sig. 'mmmm' on line 548.
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. Defining command \newopentypefeature with sig. 'mmm' on line 556.
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. LaTeX info: "xparse/define-command"
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. Defining command \aliasfontfeature with sig. 'mm' on line 577.
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. Defining command \aliasfontfeatureoption with sig. 'mmm' on line 586.
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. Defining command \newfontscript with sig. 'mm' on line 590.
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. Defining command \newfontlanguage with sig. 'mm' on line 594.
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. Defining command \DeclareFontsExtensions with sig. 'm' on line 599.
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\l__fontspec_tmp_int=\count117

(/usr/local/texlive/2016/texmf-dist/tex/latex/fontspec/fontspec.cfg)
LaTeX Info: Redefining \itshape on input line 2705.
LaTeX Info: Redefining \slshape on input line 2710.
LaTeX Info: Redefining \scshape on input line 2715.
LaTeX Info: Redefining \upshape on input line 2720.
\l__fontspec_em_int=\count118
\l__fontspec_emdef_int=\count119
LaTeX Info: Redefining \em on input line 2736.
LaTeX Info: Redefining \emph on input line 2742.
LaTeX Info: Redefining \- on input line 2746.
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. LaTeX info: "xparse/redefine-command"
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. Redefining command \oldstylenums with sig. 'm' on line 2841.
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. LaTeX info: "xparse/define-command"
. 
. Defining command \liningnums with sig. 'm' on line 2845.
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))

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! fontspec error: "font-not-found"
! 
! The font "CMU Serif" cannot be found.
! 
! See the fontspec documentation for further information.
! 
! For immediate help type H <return>.
!...............................................  

l.6 \setmainfont{CMU Serif}

|'''''''''''''''''''''''''''''''''''''''''''''''
| A font might not be found for many reasons.
| Check the spelling, where the font is installed etc. etc.
| 
| When in doubt, ask someone for help!
|...............................................

.................................................
. fontspec info: "no-scripts"
. 
. Font CMU Serif does not contain any OpenType `Script' information.
.................................................
\g__fontspec_family_CMUSerif_int=\count120
.................................................
. fontspec info: "no-font-shape"
. 
. Could not resolve font CMU Serif/BI (it probably doesn't exist).
.................................................
.................................................
. fontspec info: "no-font-shape"
. 
. Could not resolve font CMU Serif/B (it probably doesn't exist).
.................................................
.................................................
. fontspec info: "no-font-shape"
. 
. Could not resolve font CMU Serif/I (it probably doesn't exist).
.................................................

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! fontspec error: "font-not-found"
! 
! The font "CMU Serif" cannot be found.
! 
! See the fontspec documentation for further information.
! 
! For immediate help type H <return>.
!...............................................  

l.6 \setmainfont{CMU Serif}

|'''''''''''''''''''''''''''''''''''''''''''''''
| A font might not be found for many reasons.
| Check the spelling, where the font is installed etc. etc.
| 
| When in doubt, ask someone for help!
|...............................................


!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! fontspec error: "font-not-found"
! 
! The font "CMU Serif" cannot be found.
! 
! See the fontspec documentation for further information.
! 
! For immediate help type H <return>.
!...............................................  

l.6 \setmainfont{CMU Serif}

|'''''''''''''''''''''''''''''''''''''''''''''''
| A font might not be found for many reasons.
| Check the spelling, where the font is installed etc. etc.
| 
| When in doubt, ask someone for help!
|...............................................

.................................................
. fontspec info: "defining-font"
. 
. Font family 'CMUSerif(0)' created for font 'CMU Serif' with options
. [Ligatures=TeX].
. 
. This font family consists of the following NFSS series/shapes:
. - 'normal' (m/n) with NFSS spec.: <->"CMU Serif:mapping=tex-text;"
. - 'small caps'  (m/sc) with NFSS spec.: <->"CMU Serif:mapping=tex-text;"
.................................................
! Font TU/CMUSerif(0)/m/n/10.95="CMU Serif:mapping=tex-text;" at 10.95pt not lo
adable: Metric (TFM) file or installed font not found.
<to be read again> 
                   relax 
l.6 \setmainfont{CMU Serif}

I wasn't able to read the size data for this font,
so I will ignore the font specification.
[Wizards can fix TFM files using TFtoPL/PLtoTF.]
You might try inserting a different font spec;
e.g., type `I\font<same font id>=<substitute font name>'.

(./ECM_solution.aux)
\openout1 = `ECM_solution.aux'.

LaTeX Font Info:    Checking defaults for OML/cmm/m/it on input line 8.
LaTeX Font Info:    ... okay on input line 8.
LaTeX Font Info:    Checking defaults for T1/cmr/m/n on input line 8.
LaTeX Font Info:    ... okay on input line 8.
LaTeX Font Info:    Checking defaults for OT1/cmr/m/n on input line 8.
LaTeX Font Info:    ... okay on input line 8.
LaTeX Font Info:    Checking defaults for OMS/cmsy/m/n on input line 8.
LaTeX Font Info:    ... okay on input line 8.
LaTeX Font Info:    Checking defaults for OMX/cmex/m/n on input line 8.
LaTeX Font Info:    ... okay on input line 8.
LaTeX Font Info:    Checking defaults for U/cmr/m/n on input line 8.
LaTeX Font Info:    ... okay on input line 8.
LaTeX Font Info:    Checking defaults for TU/lmr/m/n on input line 8.
LaTeX Font Info:    ... okay on input line 8.
.................................................
. fontspec info: "setup-math"
. 
. Adjusting the maths setup (use [no-math] to avoid this).
.................................................
\symlegacymaths=\mathgroup4
LaTeX Font Info:    Overwriting symbol font `legacymaths' in version `bold'
(Font)                  OT1/cmr/m/n --> OT1/cmr/bx/n on input line 8.
LaTeX Font Info:    Redeclaring math accent \acute on input line 8.
LaTeX Font Info:    Redeclaring math accent \grave on input line 8.
LaTeX Font Info:    Redeclaring math accent \ddot on input line 8.
LaTeX Font Info:    Redeclaring math accent \tilde on input line 8.
LaTeX Font Info:    Redeclaring math accent \bar on input line 8.
LaTeX Font Info:    Redeclaring math accent \breve on input line 8.
LaTeX Font Info:    Redeclaring math accent \check on input line 8.
LaTeX Font Info:    Redeclaring math accent \hat on input line 8.
LaTeX Font Info:    Redeclaring math accent \dot on input line 8.
LaTeX Font Info:    Redeclaring math accent \mathring on input line 8.
LaTeX Font Info:    Redeclaring math symbol \colon on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Gamma on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Delta on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Theta on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Lambda on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Xi on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Pi on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Sigma on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Upsilon on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Phi on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Psi on input line 8.
LaTeX Font Info:    Redeclaring math symbol \Omega on input line 8.
LaTeX Font Info:    Redeclaring math symbol \mathdollar on input line 8.
LaTeX Font Info:    Redeclaring symbol font `operators' on input line 8.
LaTeX Font Info:    Encoding `OT1' has changed to `TU' for symbol font
(Font)              `operators' in the math version `normal' on input line 8.
LaTeX Font Info:    Overwriting symbol font `operators' in version `normal'
(Font)                  OT1/cmr/m/n --> TU/CMUSerif(0)/m/n on input line 8.
LaTeX Font Info:    Encoding `OT1' has changed to `TU' for symbol font
(Font)              `operators' in the math version `bold' on input line 8.
LaTeX Font Info:    Overwriting symbol font `operators' in version `bold'
(Font)                  OT1/cmr/bx/n --> TU/CMUSerif(0)/m/n on input line 8.
LaTeX Font Info:    Overwriting symbol font `operators' in version `normal'
(Font)                  TU/CMUSerif(0)/m/n --> TU/CMUSerif(0)/m/n on input line
 8.
LaTeX Font Info:    Overwriting math alphabet `\mathit' in version `normal'
(Font)                  OT1/cmr/m/it --> TU/CMUSerif(0)/m/it on input line 8.
LaTeX Font Info:    Overwriting math alphabet `\mathbf' in version `normal'
(Font)                  OT1/cmr/bx/n --> TU/CMUSerif(0)/bx/n on input line 8.
LaTeX Font Info:    Overwriting math alphabet `\mathsf' in version `normal'
(Font)                  OT1/cmss/m/n --> TU/lmss/m/n on input line 8.
LaTeX Font Info:    Overwriting math alphabet `\mathtt' in version `normal'
(Font)                  OT1/cmtt/m/n --> TU/lmtt/m/n on input line 8.
LaTeX Font Info:    Overwriting symbol font `operators' in version `bold'
(Font)                  TU/CMUSerif(0)/m/n --> TU/CMUSerif(0)/bx/n on input lin
e 8.
LaTeX Font Info:    Overwriting math alphabet `\mathit' in version `bold'
(Font)                  OT1/cmr/bx/it --> TU/CMUSerif(0)/bx/it on input line 8.

LaTeX Font Info:    Overwriting math alphabet `\mathsf' in version `bold'
(Font)                  OT1/cmss/bx/n --> TU/lmss/bx/n on input line 8.
LaTeX Font Info:    Overwriting math alphabet `\mathtt' in version `bold'
(Font)                  OT1/cmtt/m/n --> TU/lmtt/bx/n on input line 8.
Missing character: There is no n in font nullfont!
Missing character: There is no o in font nullfont!
Missing character: There is no t in font nullfont!
Missing character: There is no b in font nullfont!
Missing character: There is no o in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no d in font nullfont!
Missing character: There is no o in font nullfont!
Missing character: There is no r in font nullfont!
Missing character: There is no c in font nullfont!
Missing character: There is no a in font nullfont!
Missing character: There is no p in font nullfont!
Missing character: There is no s in font nullfont!

! Font TU/CMUSerif(0)/m/sc/10.95="CMU Serif:mapping=tex-text;" at 10.95pt not l
oadable: Metric (TFM) file or installed font not found.
<to be read again> 
                   relax 
l.12 \textsc{small caps}

I wasn't able to read the size data for this font,
so I will ignore the font specification.
[Wizards can fix TFM files using TFtoPL/PLtoTF.]
You might try inserting a different font spec;
e.g., type `I\font<same font id>=<substitute font name>'.

Missing character: There is no s in font nullfont!
Missing character: There is no m in font nullfont!
Missing character: There is no a in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no c in font nullfont!
Missing character: There is no a in font nullfont!
Missing character: There is no p in font nullfont!
Missing character: There is no s in font nullfont!

LaTeX Font Warning: Font shape `TU/CMUSerif(0)/bx/n' undefined
(Font)              using `TU/CMUSerif(0)/m/n' instead on input line 14.


LaTeX Font Warning: Font shape `TU/CMUSerif(0)/bx/sc' undefined
(Font)              using `TU/CMUSerif(0)/bx/n' instead on input line 14.

! Font TU/CMUSerif(0)/bx/n/10.95="CMU Serif:mapping=tex-text;" at 10.95pt not l
oadable: Metric (TFM) file or installed font not found.
<to be read again> 
                   relax 
l.14 \textbf{\textsc{bold small caps}}

I wasn't able to read the size data for this font,
so I will ignore the font specification.
[Wizards can fix TFM files using TFtoPL/PLtoTF.]
You might try inserting a different font spec;
e.g., type `I\font<same font id>=<substitute font name>'.

Missing character: There is no b in font nullfont!
Missing character: There is no o in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no d in font nullfont!
Missing character: There is no s in font nullfont!
Missing character: There is no m in font nullfont!
Missing character: There is no a in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no c in font nullfont!
Missing character: There is no a in font nullfont!
Missing character: There is no p in font nullfont!
Missing character: There is no s in font nullfont!
Missing character: There is no b in font nullfont!
Missing character: There is no o in font nullfont!
Missing character: There is no l in font nullfont!
Missing character: There is no d in font nullfont!
Missing character: There is no 1 in font nullfont!
[1

] (./ECM_solution.aux)

LaTeX Font Warning: Some font shapes were not available, defaults substituted.

 ) 
Here is how much of TeX's memory you used:
 9525 strings out of 493589
 210792 string characters out of 6143513
 217372 words of memory out of 5000000
 12975 multiletter control sequences out of 15000+600000
 3956 words of font info for 17 fonts, out of 8000000 for 9000
 1347 hyphenation exceptions out of 8191
 40i,4n,61p,10352b,235s stack positions out of 5000i,500n,10000p,200000b,80000s

Output written on ECM_solution.pdf (1 page).

Answer 1

The log file shows you're using XeLaTeX on a “vanilla” TeX Live, but that the CMU Serif font is not available as a system font.

Running fc-cache -fsv by itself isn't sufficient, until you also make the TeX Live fonts available to the fontconfig library.

The two commands

> sudo cp $(kpsewhich -var-value TEXMFSYSVAR)/fonts/conf/texlive-fontconfig.conf /etc/fonts/conf.d/09-texlive.conf
> sudo fc-cache -fsv

should do what you need. With > I represent the shell prompt. The file we're copying as 09-texlive.conf in /etc/fonts/conf.d contains

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
  <dir>/usr/local/texlive/2016/texmf-dist/fonts/opentype</dir>
  <dir>/usr/local/texlive/2016/texmf-dist/fonts/truetype</dir>
  <dir>/usr/local/texlive/2016/texmf-dist/fonts/type1</dir>
</fontconfig>

but this is not really important. What's important that after doing that setup, all fonts in the TeX Live main tree will be available to fontconfig and so also XeTeX will be able to find them by font name rather than only by file name.

If that doesn't work, you can always call CMU Serif by file name:

\documentclass[11pt]{article}

\usepackage[tuenc]{fontspec}

\setmainfont{cmun}[
  Extension=.otf,
  UprightFont=*rm,
  ItalicFont=*ti,
  BoldFont=*bx,
  BoldItalicFont=*bi,
]

\begin{document}

not bold or caps \textsc{small caps}

\textbf{bold} \textbf{\textsc{bold small caps}}

\textit{italic} \textsc{\textit{italic small caps}}

\textbf{\textit{bold italic}} \textbf{\textit{\textsc{bold italic small caps}}}

\end{document}

Note that CMU Serif Italic and CMU Serif BoldItalic have no small caps glyphs, so you get normal italic and bold small caps in the third and fourth lines.

If the suggested procedure for fc-cache is successful, the code

\documentclass[11pt]{article}

\usepackage[tuenc]{fontspec}

\setmainfont{CMU Serif}

\begin{document}

not bold or caps \textsc{small caps}

\textbf{bold} \textbf{\textsc{bold small caps}}

\textit{italic} \textsc{\textit{italic small caps}}

\textbf{\textit{bold italic}} \textbf{\textit{\textsc{bold italic small caps}}}

\end{document}

should work with both XeLaTeX and LuaLaTeX.