build: rewrite libdw detection without pkg-config

pkg-config expected to be more convenient way to configure libdw,
but in practice it appeared to be less portable than good old
AC_CHECK_HEADERS and AC_CHECK_LIB.

* ci/install-dependencies.sh (common_packages): Remove pkg-config.
(STACKTRACE == "libdw"): Do not install libz-dev and liblzma-dev.
* debian/control (Build-Depends): Remove pkg-config.
* m4/st_libdw.m4 (st_ARG_LIBDW, st_LIBDW): Rewrite without pkg-config.

diff --git a/ci/install-dependencies.sh b/ci/install-dependencies.sh
index e704d44e52e91888f5b07dc737965606fe084f0b..99ab56fcc5fdbd397b28186beebba4af13a4f240 100755 (executable)
--- a/ci/install-dependencies.sh
+++ b/ci/install-dependencies.sh
@@ -1,7 +1,7 @@
 #!/bin/sh -ex
 
 type sudo >/dev/null 2>&1 && sudo=sudo || sudo=
-common_packages='autoconf automake faketime file gawk gcc-multilib git gzip make pkg-config xz-utils'
+common_packages='autoconf automake faketime file gawk gcc-multilib git gzip make xz-utils'
 
 updated=
 apt_get_install()
@@ -92,7 +92,7 @@ esac
 
 case "${STACKTRACE-}" in
        libdw)
-               apt_get_install libdw-dev libz-dev liblzma-dev
+               apt_get_install libdw-dev
                ;;
        libunwind)
                apt_get_install libunwind8-dev

diff --git a/debian/control b/debian/control
index dd2db73f2e2362156a990e75d21be7d1c7c5a819..38e13a13403f14170a916bf861525a03eb390890 100644 (file)
--- a/debian/control
+++ b/debian/control
@@ -2,7 +2,7 @@ Source: strace
 Maintainer: Steve McIntyre <93sam@debian.org>
 Section: utils
 Priority: optional
-Build-Depends: libc6-dev (>= 2.2.2) [!alpha !ia64], libc6.1-dev (>= 2.2.2) [alpha ia64], gcc-multilib [amd64 i386 powerpc ppc64 ppc64el s390 s390x sparc sparc64 x32], debhelper (>= 7.0.0), gawk, pkg-config, libdw-dev, libiberty-dev, libbluetooth-dev
+Build-Depends: libc6-dev (>= 2.2.2) [!alpha !ia64], libc6.1-dev (>= 2.2.2) [alpha ia64], gcc-multilib [amd64 i386 powerpc ppc64 ppc64el s390 s390x sparc sparc64 x32], debhelper (>= 7.0.0), gawk, libdw-dev, libiberty-dev, libbluetooth-dev
 Standards-Version: 4.1.3
 Homepage: https://strace.io
 Vcs-Git: https://salsa.debian.org/debian/strace.git

diff --git a/m4/st_libdw.m4 b/m4/st_libdw.m4
index 5b80fac331b0e97802884587f1f3ac59801fc409..f33ec35688e777cf0e555edd64e7ba7faa27e07a 100644 (file)
--- a/m4/st_libdw.m4
+++ b/m4/st_libdw.m4
@@ -27,6 +27,11 @@
 
 AC_DEFUN([st_ARG_LIBDW], [dnl
 
+: ${libdw_CPPFLAGS=}
+: ${libdw_CFLAGS=}
+: ${libdw_LDFLAGS=}
+: ${libdw_LIBS=}
+
 AC_ARG_WITH([libdw],
            [AS_HELP_STRING([--with-libdw],
                            [use libdw to implement stack tracing support]
@@ -34,9 +39,9 @@ AC_ARG_WITH([libdw],
            ],
            [case "${withval}" in
             yes|no|check) ;;
-            *)
-            AC_MSG_ERROR([Use pkg-config variables instead of giving path to --with-libdw])
-            ;;
+            *) libdw_CPPFLAGS="-I${withval}/include"
+               libdw_LDFLAGS="-L${withval}/lib"
+               with_libdw=yes ;;
             esac
            ],
            [with_libdw=check]
@@ -46,60 +51,45 @@ AC_ARG_WITH([libdw],
 
 AC_DEFUN([st_LIBDW], [dnl
 
-: ${libdw_CPPFLAGS=}
-: ${libdw_CFLAGS=}
-: ${libdw_LDFLAGS=}
-: ${libdw_LIBS=}
 have_libdw=
 
-AS_IF([test "x$with_libdw" != xno],
-      [
-       dnl If libdw.pc is not available, then libdw is not new enough
-       dnl to be used for stack tracing.
-       AS_IF([test "x$with_libdw" = xyes],
-            [PKG_CHECK_MODULES([libdw], [libdw], [have_libdw=yes])],
-            [PKG_CHECK_MODULES([libdw], [libdw], [have_libdw=yes], [:])]
-           )
-      ]
-     )
-
-AS_IF([test "x$have_libdw" = xyes],
-      [
-       dnl If libdw.pc is available, check whether libdw can be used
-       dnl for stack tracing.
-       saved_CPPFLAGS="$CPPFLAGS"
+AS_IF([test "x$with_libdw" != xno && test "x$use_unwinder" = x],
+      [saved_CPPFLAGS="$CPPFLAGS"
        saved_CFLAGS="$CFLAGS"
        CPPFLAGS="$CPPFLAGS $libdw_CPPFLAGS"
        CFLAGS="$CFLAGS $libdw_CFLAGS"
 
        AC_CHECK_HEADERS([elfutils/libdwfl.h],
-                       [
-                        AC_MSG_CHECKING([for dwfl_linux_proc_attach in libdw])
-                        saved_LDFLAGS="$LDFLAGS"
-                        saved_LIBS="$LIBS"
-                        LDFLAGS="$LDFLAGS $libdw_LDFLAGS"
-                        LIBS="$LIBS $libdw_LIBS"
-
-                        AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <elfutils/libdwfl.h>]],
-                                                        [[return dwfl_linux_proc_attach(0, 0, 0)]]
-                                                       )
-                                       ],
-                                       [AC_MSG_RESULT([yes])],
-                                       [AC_MSG_RESULT([no])
-                                        AS_IF([test "x$with_libdw" = xyes],
-                                              [AC_MSG_FAILURE([failed to find dwfl_linux_proc_attach in libdw])],
-                                             )
-                                        have_libdw=
-                                       ]
-                                      )
-
-                        LIBS="$saved_LIBS"
-                        LDFLAGS="$saved_LDFLAGS"
+                       [AC_CHECK_LIB([dw], [dwfl_linux_proc_attach],
+                                     [libdw_LIBS="-ldw $libdw_LIBS"
+                                      AC_CACHE_CHECK([for elfutils version],
+                                                     [st_cv_ELFUTILS_VERSION],
+                                                     [[st_cv_ELFUTILS_VERSION="$(echo _ELFUTILS_VERSION |
+                                                                                 $CPP $CPPFLAGS -P -imacros elfutils/version.h - |
+                                                                                 grep '^[0-9]')"
+                                                       test -n "$st_cv_ELFUTILS_VERSION" ||
+                                                               st_cv_ELFUTILS_VERSION=0
+                                                     ]]
+                                                    )
+                                      AS_IF([test "$st_cv_ELFUTILS_VERSION" -ge 164],
+                                            [have_libdw=yes],
+                                            [AS_IF([test "x$with_libdw" = xyes],
+                                                   [AC_MSG_ERROR([elfutils version >= 164 is required for stack tracing support])],
+                                                   [AC_MSG_WARN([elfutils version >= 164 is required for stack tracing support])]
+                                                  )
+                                            ]
+                                           )
+                                     ],
+                                     [AS_IF([test "x$with_libdw" = xyes],
+                                            [AC_MSG_FAILURE([failed to find dwfl_linux_proc_attach in libdw])],
+                                           )
+                                     ],
+                                     [$libdw_LDFLAGS $libdw_LIBS]
+                                    )
                        ],
                        [AS_IF([test "x$with_libdw" = xyes],
                               [AC_MSG_FAILURE([failed to find elfutils/libdwfl.h])]
                              )
-                        have_libdw=
                        ]
                       )