libc/newlib: add option to compile support for float IOs

Adds support to enable/disable IOs of floating point values
(float, double, and long double).

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

config/libc/newlib.in.2

@@ -0,0 +1,17 @@
+# newlib second-part options
+
+config LIBC_NEWLIB_IO_FLOAT
+    bool
+    prompt "Enable IOs on floats and doubles"
+    default n
+    help
+      Enable support for IOs on floating point
+      values (float and double).
+
+config LIBC_NEWLIB_IO_LDBL
+    bool
+    prompt "Enable IOs on long doubles"
+    default n
+    depends on LIBC_NEWLIB_IO_FLOAT
+    help
+      Enable support for IOs on long doubles.

scripts/build/libc/newlib.sh

@@ -59,6 +59,8 @@ do_libc_headers() {
 }
 
 do_libc_start_files() {
+    local -a newlib_opts
+
     CT_DoStep INFO "Installing C library"
 
     mkdir -p "${CT_BUILD_DIR}/build-libc"
@@ -66,6 +68,18 @@ do_libc_start_files() {
 
     CT_DoLog EXTRA "Configuring C library"
 
+    if [ "${CT_LIBC_NEWLIB_IO_FLOAT}" = "y" ]; then
+        newlib_opts+=( "--enable-newlib-io-float" )
+        if [ "${CT_LIBC_NEWLIB_IO_LDBL}" = "y" ]; then
+            newlib_opts+=( "--enable-newlib-io-long-double" )
+        else
+            newlib_opts+=( "--disable-newlib-io-long-double" )
+        fi
+    else
+        newlib_opts+=( "--disable-newlib-io-float" )
+        newlib_opts+=( "--disable-newlib-io-long-double" )
+    fi
+
     # Note: newlib handles the build/host/target a little bit differently
     # than one would expect:
     #   build  : not used
@@ -79,7 +93,8 @@ do_libc_start_files() {
     "${CT_SRC_DIR}/newlib-$(libc_newlib_version)/configure" \
         --host=${CT_BUILD}                              \
         --target=${CT_TARGET}                           \
-        --prefix=${CT_PREFIX_DIR}
+        --prefix=${CT_PREFIX_DIR}                       \
+        "${newlib_opts[@]}"
 
     CT_DoLog EXTRA "Building C library"
     CT_DoExecLog ALL make ${PARALLELMFLAGS}