From f3b0a2aee21f12f3332bf598d3ba0fcbd2832f95 Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Thu, 29 Mar 2018 13:07:54 +0200 Subject: meson: Remove usage of pkg-config --variable=includedir Querying a pkg-config variable using the --variable option produces the value of the given variable as stored in the pkg-config file and should not be used to add directories to the include search path. The reason for this is that it breaks cross-compilation, because header files are installed relative to the host sysroot. pkg-config supports a PKG_CONFIG_SYSROOT_DIR environment variable that points to this sysroot and will prepend that to the path of directories in -I or -L options in pkg-config's Cflags, Libs or Libs.private keywords. However, because no context can be inferred from variable names, as opposed to the keywords with fixed meaning, the sysroot path will not be prepended to them. The build system is responsible for doing so if necessary since it is aware of the context in which the variable is used. Adding the include directory returned by pkg-config to the include path leaks build system information into the cross-build and break with very confusing errors such as this: In file included from include/misc.h:82:0, from dix/atom.c:55: /usr/include/pthread.h:682:6: warning: '__regparm__' attribute directive ignored [-Wattributes] __cleanup_fct_attribute; ^~~~~~~~~~~~~~~~~~~~~~~ or this: In file included from include/misc.h:139:0, from dix/atom.c:55: /usr/include/stdlib.h:133:8: error: '_Float128' is not supported on this target extern _Float128 strtof128 (const char *__restrict __nptr, ^~~~~~~~~ Fix this by replacing the include directory with the appropriate xproto dependency required to add the correct include directory to the compile command for subdirectories that are missing the dependency. As detailed above, this gives pkg-config the opportunity to prepend the sysroot for all paths in -I compiler options. Reviewed-by: Adam Jackson Signed-off-by: Thierry Reding --- meson.build | 1 - os/meson.build | 3 +++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/meson.build b/meson.build index 6ad98d23e..0582d6f9a 100644 --- a/meson.build +++ b/meson.build @@ -477,7 +477,6 @@ inc = include_directories( 'randr', 'render', 'xfixes', - xproto_dep.get_pkgconfig_variable('includedir') ) glx_inc = include_directories('glx') diff --git a/os/meson.build b/os/meson.build index ff3a4615b..eb8fcf55d 100644 --- a/os/meson.build +++ b/os/meson.build @@ -67,6 +67,9 @@ if srcs_libc.length() > 0 libxlibc = static_library('libxlibc', srcs_libc, include_directories: inc, + dependencies: [ + xproto_dep, + ], ) endif -- cgit v1.2.3