On 31/10/2024 13:51, Bruno Haible via Gnulib discussion list wrote:
Simon Josefsson wrote:
I merged this now, thank you!
And here's the cross-compilation handling that I promised to add.
2024-10-31 Bruno Haible <br...@clisp.org>
crc: Don't attempt to run a compiled C program when cross-compiling.
* lib/crc-generate-table.c: Don't include config.h.
* modules/crc (configure.ac): Define CROSS_COMPILING variable. Invoke
AC_PROG_MKDIR_P.
(Makefile.am): When cross-compiling, don't regenerate crc-sliceby8.h.
Don't use Gnulib modules while compiling the generator.
diff --git a/lib/crc-generate-table.c b/lib/crc-generate-table.c
index 314bf000ee..83a99baca0 100644
--- a/lib/crc-generate-table.c
+++ b/lib/crc-generate-table.c
@@ -16,8 +16,6 @@
/* Written by Sam Russell. */
-#include <config.h>
-
#include <stdio.h>
#include <stdlib.h>
diff --git a/modules/crc b/modules/crc
index d62650b28a..e8b0d91ea6 100644
--- a/modules/crc
+++ b/modules/crc
@@ -13,17 +13,33 @@ endian
configure.ac:
AC_REQUIRE([gl_CRC_SLICE_BY_8])
+CROSS_COMPILING=$cross_compiling
+AC_SUBST([CROSS_COMPILING])
+AC_PROG_MKDIR_P
Makefile.am:
lib_SOURCES += crc.c
+# Generate crc-sliceby8.h.
+# Do so only when not cross-compiling.
+# Don't use any Gnulib modules (since libgnu.a will only be available after
+# this directory is built!). Therefore, don't use any of the Automake
variables
+# $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(AM_CFLAGS)
+# $(AM_LDFLAGS). And do the compilation in a temporary directory, where
+# gnulib-generated stdio.h and stdlib.h files are not visible.
$(srcdir)/crc-sliceby8.h: $(srcdir)/crc-generate-table.c
- $(COMPILE) $(AM_LDFLAGS) $(LDFLAGS) -o crc-generate-table
$(srcdir)/crc-generate-table.c \
- && ./crc-generate-table $(srcdir)/crc-sliceby8.h-t \
- && rm -f crc-generate-table \
- && mv $(srcdir)/crc-sliceby8.h-t $(srcdir)/crc-sliceby8.h
+ if test @CROSS_COMPILING@ = no; then \
+ $(MKDIR_P) crc-tmp \
+ && abs_srcdir=`cd $(srcdir) && pwd` \
+ && (cd crc-tmp \
+ && $(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -o crc-generate-table
$$abs_srcdir/crc-generate-table.c) \
+ && crc-tmp/crc-generate-table $(srcdir)/crc-sliceby8.h-t \
+ && rm -rf crc-tmp \
+ && mv $(srcdir)/crc-sliceby8.h-t $(srcdir)/crc-sliceby8.h; \
+ fi
BUILT_SOURCES += crc-sliceby8.h
-MOSTLYCLEANFILES += crc-sliceby8.h-t crc-generate-table
+MOSTLYCLEANFILES += crc-sliceby8.h-t crc-tmp/crc-generate-table
+MOSTLYCLEANDIRS += crc-tmp
MAINTAINERCLEANFILES += crc-sliceby8.h
EXTRA_DIST += crc-sliceby8.h
Latest gnulib is failing coreutils CI because of a mismatch in mkdir && cd due
to prefixes.
In the generated Makefile I'm seeing: $(MKDIR_P) lib/crc-tmp
I.e. MKDIR_P has been processed to add in the lib prefix.
However the subsequent `cd crc-tmp` doesn't have the prefix, and the build
fails.
cheers,
Pádraig
