icc for the examples rather than gcc

document.tex

@@ -644,7 +644,7 @@ float matest(float a, float b, float c)
   \begin{block}{}
   \begin{center}
   \large
-\tt gcc -s matest.c 
+\tt icc -s matest.c 
 \normalsize
   \end{center}
   \end{block}
@@ -700,7 +700,7 @@ matest(float, float, float):
   \begin{block}{}
   \begin{center}
   \large
-\tt gcc -s -O3 matest.c 
+\tt icc -s -O3 matest.c 
 \normalsize
   \end{center}
   \end{block}
@@ -742,7 +742,7 @@ ret
   \begin{block}{}
   \begin{center}
   \large
-\tt gcc -s -O3 -xAVX2 matest.c 
+\tt icc -s -O3 -xAVX2 matest.c 
 \normalsize
   \end{center}
   \end{block}
@@ -841,7 +841,7 @@ void myfunc( double *a1, double *a2, double *prod, int c)
   \begin{block}{}
   \begin{center}
   \large
-{\tt gcc -O3 -xCORE-AVX512 matest.c } \\
+{\tt icc -O3 -xCORE-AVX512 matest.c } \\
 \normalsize
 \footnotesize
 \it