Remove quotes from around MAGICKCORE_QUANTUM_DEPTH_OBSOLETE_IN_H. (#2752)
Quoting the number 16 causes the preprocessor to generate errors and
builds to fail. It appears this number should be left unquoted.
diff --git a/configure.ac b/configure.ac
index 5662100..494b55c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -831,7 +831,7 @@
* ) AC_MSG_ERROR("Pixel quantum depth must have value of 8, 16, 32, or 64") ;;
esac
QUANTUM_DEPTH="$with_quantum_depth"
-AC_DEFINE_UNQUOTED([QUANTUM_DEPTH_OBSOLETE_IN_H],["$QUANTUM_DEPTH"],[Number of bits in a pixel Quantum (8/16/32/64)])
+AC_DEFINE_UNQUOTED([QUANTUM_DEPTH_OBSOLETE_IN_H],[$QUANTUM_DEPTH],[Number of bits in a pixel Quantum (8/16/32/64)])
AC_SUBST([QUANTUM_DEPTH])dnl
MAGICK_PCFLAGS="$MAGICK_PCFLAGS -DMAGICKCORE_QUANTUM_DEPTH=$QUANTUM_DEPTH"
CFLAGS="$CFLAGS -DMAGICKCORE_QUANTUM_DEPTH=$QUANTUM_DEPTH"