[Buildroot] [PATCH v3 1/1] package/guile: Fix build failure due to missing libiconv

[Pedro Aguilar]

When building package guile with BR2_ENABLE_LOCALE=n
we get the following error:

```
In file included from filesys.c:95:
ports-internal.h:26:10: fatal error: iconv.h: No such file or directory
   26 | #include <iconv.h>
      |          ^~~~~~~~~
compilation terminated.
```

So let's fix it by selecting BR2_PACKAGE_LIBICONV and
adding libiconv package as dependency.

Signed-off-by: Pedro Aguilar <paguilar at paguilar.org>

---
Changes v2 -> v3:
  - Improve commit message (thanks to Giulio comments)
Changes v1 -> v2:
  - Use BR2_ENABLE_LOCALE if selected, otherwise use libiconv
    as before (pointed out by Thomas and Giulio)
---
 package/guile/Config.in | 1 +
 package/guile/guile.mk  | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/package/guile/Config.in b/package/guile/Config.in
index b1182a4cee..f70e674018 100644
--- a/package/guile/Config.in
+++ b/package/guile/Config.in
@@ -9,6 +9,7 @@ config BR2_PACKAGE_GUILE
 	select BR2_PACKAGE_LIBFFI
 	select BR2_PACKAGE_GMP
 	select BR2_PACKAGE_BDWGC
+	select BR2_PACKAGE_LIBICONV if !BR2_ENABLE_LOCALE
 	help
 	  Guile is an interpreter and compiler for the Scheme
 	  programming language, a clean and elegant dialect of Lisp.
diff --git a/package/guile/guile.mk b/package/guile/guile.mk
index 0f245fca76..03420407f8 100644
--- a/package/guile/guile.mk
+++ b/package/guile/guile.mk
@@ -18,6 +18,10 @@ GUILE_CPE_ID_VENDOR = gnu
 GUILE_DEPENDENCIES = host-guile libunistring libffi gmp bdwgc host-pkgconf
 HOST_GUILE_DEPENDENCIES = host-libunistring host-libffi host-gmp host-bdwgc host-flex host-pkgconf host-gettext
 
+ifeq ($(BR2_ENABLE_LOCALE),)
+GUILE_DEPENDENCIES += libiconv
+endif
+
 # The HAVE_GC* CFLAGS specify that we will use internal callbacks
 # instead of the ones provided by
 # bdwgc. Eg. HAVE_GC_SET_FINALIZER_NOTIFIER specifies that we won't
-- 
2.25.1