Enable -Wall -Wno-unknown-pragmas compiler setting

Enable `-Wall -Wno-unknown-pragmas` compiler setting to show warnings
during build.

Supress "unknown-pragmas" warning though because it's legitimely used
for openmp support.

Signed-off-by: Olli <oparviai'at'iki.fi>

CMakeLists.txt

@@ -7,7 +7,7 @@ if(MSVC)
   set(COMPILE_DEFINITIONS /O2 /fp:fast)
   set(COMPILE_OPTIONS )
 else()
-  set(COMPILE_OPTIONS -Ofast)
+  set(COMPILE_OPTIONS -Ofast -Wall -Wno-unknown-pragmas)
 endif()
 
 #####################

README.html

@@ -975,6 +975,7 @@
       <li> Michael Pruett</li>
       <li> Rajeev Puran</li>
       <li> RJ Ryan</li>
+      <li> Serge Sans Paille</li>
       <li> John Sheehy</li>
       <li> Tim Shuttleworth</li>
       <li> Albert Sirvent</li>

configure.ac

@@ -33,7 +33,7 @@ AC_LANG(C++)
 
 # Compiler flags. Apply -Ofast (implies -O3 -ffast-math) to allow gcc autovectorization
 # generate effective SIMD code.
-CXXFLAGS+=" -Ofast"
+CXXFLAGS+=" -Ofast -Wall -Wno-unknown-pragmas"
 
 # Set AR_FLAGS to avoid build warning "ar: `u' modifier ignored since `D' is the default (see `U')"
 AR_FLAGS='cr'