autoconf: Implement release tarball detection. Fixes #257.

This should finally allow us to address all cases of build errors due to
differences between release tarballs and building from git.

See also https://github.com/NixOS/nix/issues/506#issuecomment-507312587
This commit is contained in:
Niklas Hambüchen 2019-07-03 04:28:06 +02:00
parent cd8bc06e87
commit 82b7f0e840

View file

@ -5,6 +5,19 @@ AC_CONFIG_AUX_DIR(config)
AC_PROG_SED
# Detect building from release tarballs (we need less dependencies then)
# by checking for the `.dist-files` file present only in release tarballs
# (created in release.nix).
# For example, we don't need to build the manual or run bison/flex
# parser generators for release tarballs, as those have them pre-generated.
AC_MSG_CHECKING([whether we are building from a release tarball (.dist-files existence)])
if test -f .dist-files; then
AC_MSG_RESULT(yes; will not require tools that are not needed for building from release tarballs)
building_from_release_tarball=yes;
else
AC_MSG_RESULT(no)
fi
# Construct a Nix system name (like "i686-linux").
AC_CANONICAL_HOST
AC_MSG_CHECKING([for the canonical Nix system name])
@ -119,14 +132,13 @@ if test -z "$$1"; then
fi
])
# Note: Usage of `AC_PATH_PROG(..., ..., false)` indicates that this program
# is not required in all cases. (e.g. not when building from a release tarball).
# The use of `false` isn't ideal, because when used somewhere in the build it
# will silently fail without error message; this should be improved.
NEED_PROG(bash, bash)
NEED_PROG(patch, patch)
AC_PATH_PROG(flex, flex, false)
AC_PATH_PROG(bison, bison, false)
if test "x$building_from_release_tarball" != x"yes"; then
# Parser generators are pre-built in release tarballs.
NEED_PROG(flex, flex)
NEED_PROG(bison, bison)
fi
NEED_PROG(sed, sed)
NEED_PROG(tar, tar)
NEED_PROG(bzip2, bzip2)
@ -260,7 +272,8 @@ AC_ARG_ENABLE(doc-gen, AC_HELP_STRING([--disable-doc-gen],
doc_generate=$enableval, doc_generate=yes)
AC_SUBST(doc_generate)
if test "$doc_generate" = yes; then
# The manual is pre-generated in release tarballs.
if test "$doc_generate" = yes && test "x$building_from_release_tarball" != x"yes"; then
# Programs required to build the manual
NEED_PROG(xmllint, xmllint)
NEED_PROG(xsltproc, xsltproc)