diff --git a/src/fileio.c b/src/fileio.c
index 17ad22af..40a443d2 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -176,7 +176,7 @@ static void print_ihex_extended_addr(int n_64k, FILE *outf) {
  * Return the maximum memory address within mem->buf that was read from
  * plus one. If an error occurs, return -1.
  */
-static int b2ihex(const unsigned char *buf, Segment_t *segp, Segorder_t where,
+static int b2ihex(const unsigned char *buf, const Segment_t *segp, Segorder_t where,
   int recsize, int startaddr, const char *outfile_unused, FILE *outf,
   FILEFMT ffmt) {
 
@@ -339,7 +339,7 @@ static int ihex_readrec(struct ihexsrec *ihex, char * rec) {
  * plus one. If an error occurs, return -1.
  */
 static int ihex2b(const char *infile, FILE *inf, const AVRMEM *mem,
-  Segment_t *segp, unsigned int fileoffset, FILEFMT ffmt) {
+  const Segment_t *segp, unsigned int fileoffset, FILEFMT ffmt) {
 
   const char *errstr;
   unsigned int nextaddr, baseaddr, maxaddr;
@@ -458,7 +458,7 @@ static unsigned int cksum_srec(const unsigned char *buf, int n, unsigned addr, i
 
 
 // Binary to Motorola S-Record, see https://en.wikipedia.org/wiki/SREC_(file_format)
-static int b2srec(const AVRMEM *mem, Segment_t *segp, Segorder_t where,
+static int b2srec(const AVRMEM *mem, const Segment_t *segp, Segorder_t where,
   int recsize, int startaddr, const char *outfile_unused, FILE *outf) {
 
   const unsigned char *buf;
@@ -609,7 +609,7 @@ static int srec_readrec(struct ihexsrec *srec, char *rec) {
 
 // Motorola S-Record to binary
 static int srec2b(const char *infile, FILE * inf,
-  const AVRMEM *mem, Segment_t *segp, unsigned int fileoffset) {
+  const AVRMEM *mem, const Segment_t *segp, unsigned int fileoffset) {
 
   const char *errstr;
   unsigned int nextaddr, maxaddr;
@@ -823,7 +823,7 @@ static int elf_mem_limits(const AVRMEM *mem, const AVRPART *p,
 
 // ELF format to binary (the memory segment to read into is ignored)
 static int elf2b(const char *infile, FILE *inf, const AVRMEM *mem,
-  const AVRPART *p, Segment_t *segp_unused, unsigned int fileoffset_unused) {
+  const AVRPART *p, const Segment_t *segp_unused, unsigned int fileoffset_unused) {
 
   Elf *e;
   int rv = 0, size = 0;
@@ -1033,7 +1033,7 @@ done:
 
 // Read/write binary files and return highest memory addr set + 1
 static int fileio_rbin(struct fioparms *fio, const char *filename, FILE *f,
-  const AVRMEM *mem, Segment_t *segp) {
+  const AVRMEM *mem, const Segment_t *segp) {
 
   int rc;
   switch (fio->op) {
@@ -1061,7 +1061,7 @@ static int fileio_rbin(struct fioparms *fio, const char *filename, FILE *f,
 
 
 static int fileio_imm(struct fioparms *fio, const char *fname, FILE *f_unused,
- const AVRMEM *mem, Segment_t *segp) {
+ const AVRMEM *mem, const Segment_t *segp) {
 
   char *tok, *p, *line;
   const char *errstr;
@@ -1100,7 +1100,7 @@ static int fileio_imm(struct fioparms *fio, const char *fname, FILE *f_unused,
 
 
 static int fileio_ihex(struct fioparms *fio, const char *filename, FILE *f,
-  const AVRMEM *mem, Segment_t *segp, FILEFMT ffmt, Segorder_t where) {
+  const AVRMEM *mem, const Segment_t *segp, FILEFMT ffmt, Segorder_t where) {
 
   int rc;
 
@@ -1123,7 +1123,7 @@ static int fileio_ihex(struct fioparms *fio, const char *filename, FILE *f,
 
 
 static int fileio_srec(struct fioparms *fio, const char *filename, FILE *f,
-  const AVRMEM *mem, Segment_t *segp, Segorder_t where) {
+  const AVRMEM *mem, const Segment_t *segp, Segorder_t where) {
 
   int rc;
 
@@ -1147,7 +1147,7 @@ static int fileio_srec(struct fioparms *fio, const char *filename, FILE *f,
 
 #ifdef HAVE_LIBELF
 static int fileio_elf(struct fioparms *fio, const char *filename, FILE *f,
-  const AVRMEM *mem, const AVRPART *p, Segment_t *segp) {
+  const AVRMEM *mem, const AVRPART *p, const Segment_t *segp) {
 
   int rc;
 
@@ -1171,7 +1171,7 @@ static int fileio_elf(struct fioparms *fio, const char *filename, FILE *f,
 #endif
 
 
-static int b2num(const char *filename, FILE *f, const AVRMEM *mem, Segment_t *segp, FILEFMT fmt) {
+static int b2num(const char *filename, FILE *f, const AVRMEM *mem, const Segment_t *segp, FILEFMT fmt) {
   const char *prefix;
   int base;
 
@@ -1235,7 +1235,7 @@ static int b2num(const char *filename, FILE *f, const AVRMEM *mem, Segment_t *se
 }
 
 
-static int num2b(const char *filename, FILE *f, const AVRMEM *mem, Segment_t *segp) {
+static int num2b(const char *filename, FILE *f, const AVRMEM *mem, const Segment_t *segp) {
   const char *geterr = NULL;
   char *line;
   int n = segp->addr, end = segp->addr + segp->len;
@@ -1271,7 +1271,7 @@ static int num2b(const char *filename, FILE *f, const AVRMEM *mem, Segment_t *se
 
 
 static int fileio_num(struct fioparms *fio, const char *filename, FILE *f,
-  const AVRMEM *mem, Segment_t *segp, FILEFMT fmt) {
+  const AVRMEM *mem, const Segment_t *segp, FILEFMT fmt) {
 
   switch (fio->op) {
     case FIO_WRITE:
@@ -1443,7 +1443,7 @@ int fileio(int op, const char *filename, FILEFMT format,
   if(size < 0 || op == FIO_READ || FIO_READ_FOR_VERIFY)
     size = mem->size;
 
-  Segment_t seg = {0, size};
+  const Segment_t seg = {0, size};
   return fileio_segments(op, filename, format, p, mem, 1, &seg);
 }
 
@@ -1478,7 +1478,7 @@ int segmemt_normalise(AVRMEM *mem, Segment_t *segp) {
 }
 
 
-int fileio_segments(int oprwv, const char *filename, FILEFMT format,
+static int fileio_segments_normalise(int oprwv, const char *filename, FILEFMT format,
   const AVRPART *p, AVRMEM *mem, int n, Segment_t *seglist) {
 
   int op, rc;
@@ -1628,3 +1628,15 @@ int fileio_segments(int oprwv, const char *filename, FILEFMT format,
 
   return rc;
 }
+
+int fileio_segments(int oprwv, const char *filename, FILEFMT format,
+  const AVRPART *p, AVRMEM *mem, int n, const Segment_t *list) {
+
+  Segment_t *seglist = cfg_malloc(__func__, n*sizeof*seglist);
+  memcpy(seglist, list, n*sizeof*seglist);
+  int ret = fileio_segments_normalise(oprwv, filename, format, p, mem, n, seglist);
+  free(seglist);
+
+  return ret;
+}
+
diff --git a/src/libavrdude.h b/src/libavrdude.h
index 33d22f69..b5c0e7ed 100644
--- a/src/libavrdude.h
+++ b/src/libavrdude.h
@@ -1039,7 +1039,7 @@ int fileio(int oprwv, const char *filename, FILEFMT format,
 int segmemt_normalise(AVRMEM *mem, Segment_t *segp);
 
 int fileio_segments(int oprwv, const char *filename, FILEFMT format,
-  const AVRPART *p, AVRMEM *mem, int n, Segment_t *seglist);
+  const AVRPART *p, AVRMEM *mem, int n, const Segment_t *seglist);
 
 #ifdef __cplusplus
 }