[binutils-gdb] Fix Rust lex selftest when using libiconv

[binutils-gdb] Fix Rust lex selftest when using libiconv

[Tom Tromey]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=775d36a916c1be042ceb67fc6ea22f53a9f5e331

commit 775d36a916c1be042ceb67fc6ea22f53a9f5e331
Author: Tom Tromey <tromey@adacore.com>
Date:   Thu Sep 30 12:53:55 2021 -0600

    Fix Rust lex selftest when using libiconv
    
    The Rust lex selftest fails on our Windows build.  I tracked this down
    to a use of UTF-32 as a parameter to convert_between_encodings.  Here,
    iconv_open succeeds, but the actual conversion of a tab character
    fails with EILSEQ.  I suspect that "UTF-32" is being interpreted as
    big-endian, as changing the call to use "UTF-32LE" makes it work.
    This patch implements this fix.

Diff:
---
 gdb/rust-parse.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/gdb/rust-parse.c b/gdb/rust-parse.c
index 539e1c8256d..e12bf29a71d 100644
--- a/gdb/rust-parse.c
+++ b/gdb/rust-parse.c
@@ -695,9 +695,16 @@ rust_parser::lex_string ()
 	  if (is_byte)
 	    obstack_1grow (&obstack, value);
 	  else
-	    convert_between_encodings ("UTF-32", "UTF-8", (gdb_byte *) &value,
-				       sizeof (value), sizeof (value),
-				       &obstack, translit_none);
+	    {
+#if WORDS_BIGENDIAN
+#define UTF32 "UTF-32BE"
+#else
+#define UTF32 "UTF-32LE"
+#endif
+	      convert_between_encodings (UTF32, "UTF-8", (gdb_byte *) &value,
+					 sizeof (value), sizeof (value),
+					 &obstack, translit_none);
+	    }
 	}
       else if (pstate->lexptr[0] == '\0')
 	error (_("Unexpected EOF in string"));