diff --git a/DESCRIPTION b/DESCRIPTION
index 2f1bc91..751d1f4 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: vcfppR
 Title: Rapid Manipulation of the Variant Call Format (VCF)
-Version: 0.3.7
+Version: 0.3.8
 Authors@R: c(
     person("Zilong", "Li", , "zilong.dk@gmail.com", role = c("aut", "cre"),
            comment = c(ORCID = "0000-0001-5859-2078")),
diff --git a/NEWS.md b/NEWS.md
index 3c64be6..ca5f10a 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,7 @@
+# vcfppR 0.3.8
+
+* fix issues on M1 Mac
+
 # vcfppR 0.3.7
 
 * add `vcfreader@rmFormatTag()`
diff --git a/cran-comments.md b/cran-comments.md
index 1243974..c174243 100644
--- a/cran-comments.md
+++ b/cran-comments.md
@@ -1,10 +1,4 @@
-Fix the following issues.
+Fix issues on M1 Mac 
 
-1. Removed the redundant "in R" in the title.
-2. Wrote 'C++', 'htslib' 'vcfpp.h' in single quotes
-3. Updated the .Rd files by adding \value and \examples for exported methods and classes
-4. Added the authors of htslib as 'cph' in ‘Authors@R’ 
+https://cran.r-project.org/web/checks/check_results_vcfppR.html
 
-Comments about documenting the C++ class:
-
-I've documented each method of the C++ class by using a nested structure inside the \section(Fields), which is the only way I found that can document the C++ class by doxygen2 automatically.
diff --git a/src/Makevars b/src/Makevars
index 3b21c51..15fb960 100644
--- a/src/Makevars
+++ b/src/Makevars
@@ -13,8 +13,8 @@ CXX=$(shell "R CMD config CXX")
 AR=$(shell "R CMD config AR")
 RANLIB=$(shell "R CMD config RANLIB")
 LDFLAGS=$(shell "R CMD config LDFLAGS")
-# CFLAGS=$(shell "R CMD config CFLAGS")
-# CPPFLAGS=$(shell "R CMD config CPPFLAGS")
+CFLAGS=$(shell "R CMD config CFLAGS")
+CPPFLAGS=$(shell "R CMD config CPPFLAGS")
 
 HTSLIB:
 	(cd ${HTSLIB_DIR} && $(MAKE) -f Makefile.vcfppR libhts.a && cd ..)
diff --git a/src/htslib-1.18/htscodecs/htscodecs/rANS_static4x16pr.c b/src/htslib-1.18/htscodecs/htscodecs/rANS_static4x16pr.c
index 732d9f5..9a38fd9 100644
--- a/src/htslib-1.18/htscodecs/htscodecs/rANS_static4x16pr.c
+++ b/src/htslib-1.18/htscodecs/htscodecs/rANS_static4x16pr.c
@@ -1015,7 +1015,7 @@ unsigned char *(*rans_dec_func(int do_simd, int order))
 #include <processthreadsapi.h>
 #endif
 
-static inline int have_neon() {
+static inline int have_neon(void) {
 #if defined(__linux__) && defined(__arm__)
     return (getauxval(AT_HWCAP) & HWCAP_NEON) != 0;
 #elif defined(__linux__) && defined(__aarch64__)