Merge branch 'maint'

[bison.git] / README-hacking

diff --git a/README-hacking b/README-hacking
index bb91ac063ac9cba844b42f82cb914c082350c010..988bd3044cb778ddf1e23f56b13eb984d2d07c53 100644 (file)
--- a/README-hacking
+++ b/README-hacking
@@ -35,6 +35,13 @@ of the .output file etc.  This excludes impossible error messages
 (comparable to assert/abort), and all the --trace output which is
 meant for the maintainers only.
 
+** Horizontal tabs
+Do not add horizontal tab characters to any file in Bison's repository
+except where required.  For example, do not use tabs to format C code.
+However, make files, ChangeLog, and some regular expressions require
+tabs.  Also, test cases might need to contain tabs to check that Bison
+properly processes tabs in its input.
+
 
 * Working from the repository
 
@@ -168,6 +175,19 @@ decide whether to update.
 ** make check
 Use liberally.
 
+** Typical errors
+If the test suite shows failures such as the following one
+
+  .../bison/lib/getopt.h:196:8: error: redefinition of 'struct option'
+  /usr/include/getopt.h:54:8: error: previous definition of 'struct option'
+
+it probably means that some file was compiled without
+AT_DATA_SOURCE_PROLOGUE.  This error is due to the fact that our -I options
+pick up gnulib's replacement headers, such as getopt.h, and this will go
+wrong if config.h was not included first.
+
+See tests/local.at for details.
+
 ** make maintainer-check-valgrind
 This target uses valgrind both to check bison, and the generated parsers.
 
@@ -226,6 +246,9 @@ release:
   that it does not make sense for glr.c, which should be ANSI, but
   currently is actually GNU C, nor for lalr1.cc.
 
+- Test with a very recent version of GCC for both C and C++.  Testing
+  with older versions that are still in use is nice too.
+
 
 * Release Procedure
 This section needs to be updated to take into account features from