Some additions to the README file

diff --git a/README b/README
index cf5fbdb137a0f74d16755ad17b5c67fff2485702..8fdbf082527c0b074542f743e629cd69c5812d1d 100644 (file)
--- a/README
+++ b/README
@@ -69,6 +69,7 @@ will install all prerequisites for building yosys:
        $ sudo apt-get install libqt4-dev
        $ sudo apt-get install mercurial
        $ sudo apt-get install iverilog
+       $ sudo apt-get install graphviz
 
 To configure the build system to use a specific set of compiler and
 build configuration, use one of
@@ -89,6 +90,9 @@ To build Yosys simply type 'make' in this directory.
        $ make test
        $ sudo make install
 
+If you encounter any problems during build, make sure to check the section
+"Workarounds for known build problems" at the end of this README file.
+
 To also build and install ABC (recommended) use the following commands:
 
        $ make abc
@@ -258,6 +262,21 @@ Verilog Attributes and non-standard features
   __YOSYS_ENABLE_DEFATTR__ must be set in order for this feature to be active.
 
 
+Workarounds for known build problems
+====================================
+
+You might get an error message like this one during build when building with
+a recent version of gcc:
+
+       /usr/include/minisat/utils/Options.h:285:29: error:
+       unable to find string literal operator ‘operator"" PRIi64’
+
+This is a bug in the minisat header. It can be fixed by adding spaces before
+and after each occurance of PRIi64 in the header file:
+
+        sudo sed -i 's/PRIi64/ & /' /usr/include/minisat/utils/Options.h
+
+
 TODOs / Open Bugs
 =================