Commit 2500ebfc89 (util: fix make dependencies for subst) broke cross compilation because it unconditionally used config.h without setting a includes path so that the config.h file could be found. The proposed fix of adding the include path (such as was proposed at http://patchwork.ozlabs.org/patch/355662/ or in Debian Bug #753375) aren't really the right fix, since the information in config.h is for the target environment, and not the build environment. So using config.h when building helper programs used as part of the build can potentially cause more problems than it solves. In general, build helpers must be written to be as portable as possible, and to not require any autoconf defined #ifdef's whenever possible. The subst program broke this rule to (1) address a Coverity security complaint by using futimes if is present, and (2) to preserve the nanosecond portion of the file timestamp. Oh, well. We won't be able to do the latter when cross compiling, and as to the former, if an attacker has write access to your build tree while you are building programs that will be run as root, you've got bigger problems. :-) Fix the problem that commit 2500ebfc89 was trying to address by explicitly adding @DEFS@ to CFLAGS, so that -DHAVE_CONFIG_H is passed to make depend. This fixes up the make depend without forcing the use of config.h when cross-compiling. Addresses-Debian-Bug: #753375 Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> Cc: Helmut Grohne <helmut@xxxxxxxxxx> Cc: Gustavo Zacarias <gustavo@xxxxxxxxxxxxxxx> Cc: 753375@xxxxxxxxxxxxxxx --- MCONFIG.in | 2 +- util/subst.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/MCONFIG.in b/MCONFIG.in index 3c1a4cb..7393379 100644 --- a/MCONFIG.in +++ b/MCONFIG.in @@ -67,7 +67,7 @@ pkgconfigdir = $(libdir)/pkgconfig CC = @CC@ BUILD_CC = @BUILD_CC@ -CFLAGS = @CFLAGS@ +CFLAGS = @CFLAGS@ @DEFS@ CPPFLAGS = @INCLUDES@ ALL_CFLAGS = $(CPPFLAGS) $(CFLAGS) LDFLAGS = @LDFLAGS@ diff --git a/util/subst.c b/util/subst.c index 6a5eab1..6244831 100644 --- a/util/subst.c +++ b/util/subst.c @@ -5,7 +5,9 @@ * */ +#ifdef HAVE_CONFIG_H #include "config.h" +#endif #include <stdio.h> #include <errno.h> #include <stdlib.h> -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
