From: rschulz Date: Wed, 13 Jul 2005 13:56:14 +0000 (+0000) Subject: changed cygwin linkage behaviour, if dynamic libraries are used (see change notes) X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9e70f1719bdbd274c8208b6cd506835dc14f9767;p=dealii-svn.git changed cygwin linkage behaviour, if dynamic libraries are used (see change notes) git-svn-id: https://svn.dealii.org/trunk@11137 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/aclocal.m4 b/deal.II/aclocal.m4 index a2738443df..f432ad077d 100644 --- a/deal.II/aclocal.m4 +++ b/deal.II/aclocal.m4 @@ -378,8 +378,15 @@ AC_DEFUN(DEAL_II_SET_CXX_FLAGS, dnl ;; *cygwin* ) + dnl On Cygwin, when using shared libraries, there might occur + dnl difficulties when linking libraries for several dimensions, + dnl as some symbols are defined in all of them. This leads to a + dnl linker error. We force the linker to ignore multiple symbols, + dnl but of course this might lead to strange program behaviour if + dnl you accidentally defined one symbol multiple times... + dnl (added 2005/07/13, Ralf B. Schulz) CXXFLAGSPIC= - LDFLAGSPIC= + LDFLAGSPIC=-Xlinker --allow-multiple-definition ;; *) @@ -1980,7 +1987,7 @@ AC_DEFUN(DEAL_II_CHECK_ABORT, dnl AC_TRY_COMPILE( [ #include -extern "C" void abort () {} +extern "C" void abort () { for(;;) ; } ], [ ], diff --git a/deal.II/doc/news/changes.html b/deal.II/doc/news/changes.html index 8b372db8ef..de8f9a1246 100644 --- a/deal.II/doc/news/changes.html +++ b/deal.II/doc/news/changes.html @@ -142,6 +142,17 @@ inconvenience this causes.

General

    +
  1. + Changed: Cygwin has problems linking against deal.II DLLs if you + link against more than one dimension dependent library. The linker + might issue error messages about multiple defined symbols. This is now + detected, and the linker is forced to ignore these errors. However, if + you accidentally defined symbols twice you might have a hard time + debugging now... In this case remove the -Xlinker + --allow-multiple-definition flag from Make.global_options. +
    + (Ralf B. Schulz, 2005/07/13) +

  2. Changed: Under Cygwin, linking against LAPACK and UMFPACK did not work. This is now fixed in the Makefiles. Changes only