From c504d90c1159bd0fadd37bb3098ecf8622d0b13c Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Mon, 12 Jan 2009 16:30:32 +0000 Subject: [PATCH] * Support i686-linux builds directly on x86_64-linux Nix installations. This is implemented using the personality() syscall, which causes uname to return "i686" in child processes. --- configure.ac | 7 ++++++- src/libstore/build.cc | 19 ++++++++++++++++++- 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/configure.ac b/configure.ac index fdf898640..44c22c19b 100644 --- a/configure.ac +++ b/configure.ac @@ -100,12 +100,17 @@ AC_CHECK_HEADERS([sys/mount.h], [], [], ]) -# Check for +# Check for . AC_LANG_PUSH(C++) AC_CHECK_HEADERS([locale], [], [], []) AC_LANG_POP(C++) +# Check whether we have the personality() syscall, which allows us to +# do i686-linux builds on x86_64-linux machines. +AC_CHECK_HEADERS([sys/personality.h]) + + AC_DEFUN([NEED_PROG], [ AC_PATH_PROG($1, $2) diff --git a/src/libstore/build.cc b/src/libstore/build.cc index f015b878c..db2bed6d0 100644 --- a/src/libstore/build.cc +++ b/src/libstore/build.cc @@ -40,6 +40,12 @@ #define CHROOT_ENABLED HAVE_CHROOT && HAVE_UNSHARE && HAVE_SYS_MOUNT_H && defined(MS_BIND) && defined(CLONE_NEWNS) +#if HAVE_SYS_PERSONALITY_H +#include +#define CAN_DO_LINUX32_BUILDS +#endif + + namespace nix { using std::map; @@ -1474,7 +1480,11 @@ void DerivationGoal::startBuilder() format("building path(s) %1%") % showPaths(outputPaths(drv.outputs))) /* Right platform? */ - if (drv.platform != thisSystem) + if (drv.platform != thisSystem +#ifdef CAN_DO_LINUX32_BUILDS + && !(drv.platform == "i686-linux" && thisSystem == "x86_64-linux") +#endif + ) throw BuildError( format("a `%1%' is required to build `%3%', but I am a `%2%'") % drv.platform % thisSystem % drvPath); @@ -1806,6 +1816,13 @@ void DerivationGoal::startBuilder() initChild(); +#ifdef CAN_DO_LINUX32_BUILDS + if (drv.platform == "i686-linux" && thisSystem == "x86_64-linux") { + if (personality(PER_LINUX32_3GB) == -1) + throw SysError("cannot set i686-linux personality"); + } +#endif + /* Fill in the environment. */ Strings envStrs; for (Environment::const_iterator i = env.begin();