bug#78882: stty.c compilation error

Hi,

The coreutils CI fails today on OpenBSD and Solaris. (The previous build,
a week ago, succeeded.)

Compilation error on OpenBSD:

cc  -I. -I.. -I./lib  -Ilib -I../lib -Isrc -I../src -I/usr/local/include -Wall  -Wno-format-extra-args -Wno-implicit-const-int-float-conversion -Wno-tautological-constant-out-of-range-compare -g -O2 -MT src/stty.o -MD -MP -MF $depbase.Tpo -c -o src/stty.o ../src/stty.c &&\
mv -f $depbase.Tpo $depbase.Po
In file included from ../src/stty.c:2177:
src/speedlist.h:156:4: error: unterminated conditional directive
#  ifdef B4000000n      case 4000000: return B4000000;n#  endif
   ^
src/speedlist.h:155:4: error: unterminated conditional directive
#  ifdef B3500000n      case 3500000: return B3500000;n#  endif
   ^
...

Compilation error on Solaris 11.4:

gcc -m64  -I. -I.. -I./lib  -Ilib -I../lib -Isrc -I../src  -Wall -D_REENTRANT  -g -O2 -MT src/stty.o -MD -MP -MF $depbase.Tpo -c -o src/stty.o ../src/stty.c &&\
mv -f $depbase.Tpo $depbase.Po
In file included from ../src/stty.c:2177:
src/speedlist.h: In function ‘baud_to_value’:
src/speedlist.h:60:19: warning: extra tokens at end of #ifdef directive
   60 | #  ifdef B0n      case B0: return 0;n#  endif
      |                   ^~~~
src/speedlist.h:156: error: unterminated #ifdef
  156 | #  ifdef B4000000n      case 4000000: return B4000000;n#  endif
src/speedlist.h:155: error: unterminated #ifdef
...


It looks like the 'speedgen' script, added in commit
357fda90d15fd3f7dba61e1ab322b183a48d0081, produces this invalid C code.

With GNU sed:

$ echo 100 | sed -e 's/^.*$/#  ifdef B&\n      case B&: return &;\n#  endif/'
#  ifdef B100
      case B100: return 100;
#  endif

With OpenBSD sed and Solaris sed:

$ echo 100 | sed -e 's/^.*$/#  ifdef B&\n      case B&: return &;\n#  endif/'
#  ifdef B100n      case B100: return 100;n#  endif

The attached patch fixes it.

From 4be6c54b010b05b143ffcfd2368b634f20be4dad Mon Sep 17 00:00:00 2001
From: Bruno Haible <[email protected]>
Date: Mon, 23 Jun 2025 22:59:47 +0200
Subject: [PATCH] build: Fix compilation error on OpenBSD and Solaris

* src/speedgen: Use 'printf', not 'sed', to emit code with newlines.
---
 src/speedgen | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/speedgen b/src/speedgen
index f1647d9f0..d14ed3f6b 100755
--- a/src/speedgen
+++ b/src/speedgen
@@ -49,8 +49,9 @@ baud_to_value (speed_t speed)
     {
 EOF
 
-sed -e 's/^.*$/#  ifdef B&\n      case B&: return &;\n#  endif/' \
-    < "$tmp" >> "$out"
+while read n; do
+  printf '#  ifdef B%s\n      case B%s: return %s;\n#  endif\n' "$n" "$n" "$n"
+done < "$tmp" >> "$out"
 
 cat >> "$out" <<'EOF'
       default: return -1;
@@ -72,8 +73,9 @@ value_to_baud (unsigned long int value)
     {
 EOF
 
-sed -e 's/^.*$/#  ifdef B&\n      case &: return B&;\n#  endif/' \
-    < "$tmp" >> "$out"
+while read n; do
+  printf '#  ifdef B%s\n      case %s: return B%s;\n#  endif\n' "$n" "$n" "$n"
+done < "$tmp" >> "$out"
 
 cat >> "$out" <<'EOF'
       default: return (speed_t) -1;
-- 
2.43.0