Hello Amittai, * Amittai Aviram wrote on Tue, Jan 11, 2011 at 08:17:39AM CET: > I want to add a few files to the gcc source tree and build and test > the resulting gcc, but I am having trouble finding my way around the > Automake system. [...] > Then I ran automake in order to produce (I thought) the corresponding > Makefile.in, and got this error: > > $ automake [...] > configure.ac:5: error: Please use exactly Autoconf 2.64 instead of 2.65. > ../config/override.m4:34: _GCC_AUTOCONF_VERSION_CHECK is expanded from... > configure.ac:5: the top level > autom4te: /usr/bin/m4 failed with exit status: 1 > automake: autoconf failed with exit status: 1 [...] > It seems to me that a version 2.65 autoconf should be sufficiently > backward compatible to deal with input for the previous minor version. > So why am I running into this problem and what can I do about it? The GCC tree requires an exact version, rather than a minimal version of Autoconf, because the generated files are committed into version control and there would be spurious differences due to version skew all the time otherwise; this used to be the case before the check was put into place. However, the config/override.m4 macro file also documents how this check can be overridden (at the location given in the error message): by m4_define'ing _GCC_AUTOCONF_VERSION to the version you use early. Thus, you could either patch override.m4 right away and enter your version there, or do that in the configure.ac file (before AC_INIT) which belongs to the part of the GCC tree you are working on. Hope that helps. Cheers, Ralf
