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diff --git a/contrib/gdb/libiberty/README b/contrib/gdb/libiberty/README deleted file mode 100644 index 5081bbac1968..000000000000 --- a/contrib/gdb/libiberty/README +++ /dev/null @@ -1,129 +0,0 @@ -This directory contains the -liberty library of free software. -It is a collection of subroutines used by various GNU programs. -Current members include: - - getopt -- get options from command line - obstack -- stacks of arbitrarily-sized objects - strerror -- error message strings corresponding to errno - strtol -- string-to-long conversion - strtoul -- string-to-unsigned-long conversion - -We expect many of the GNU subroutines that are floating around to -eventually arrive here. - -To build the library, do: - - ./configure HOSTTYPE - make - -Please report bugs and fixes to "bug-gnu-utils@prep.ai.mit.edu". Thank you. - -ADDING A NEW FILE -================= - -There are two sets of files: Those that are "required" will be -included in the library for all configurations, while those -that are "optional" will be included in the library only if "needed." - -To add a new required file, edit Makefile to add the source file -name to CFILES and the object file to REQUIRED_OFILES. - -Adding a new optional file is more fragile. As a general rule, -an optional file will be included in the library if it provides -functionality missing in the "standard" C library. -For most hosts, the Makefile automatically figures out which -functionality is missing by compiling and linking a dummy test -program, and examining the error messages. - -So to get this to work, you should do the following: - -1) Select one function defined in the file you're adding. -For example, the getcwd function. -2) Add that function to the list in the file functions.def. -3) The name of the new file must be the same as the function -you've chosen with the .c suffix added. E.g. getcwd() must be -defined in getcwd.c. (The file can define other functions as well.) -4) In Makefile.in, add the name of the source file (e.g. getcwd.c) -to CFILES. - -The file you've added (e.g. getcwd.c) should compile and work -on all hosts where it is needed (e.g. not found when linking -the dummy.c program). It does not have to work or even -compile on hosts where it is not needed. - -HOW THE AUTOMATIC CONFIGURATION WORKS -===================================== - -The libiberty.a target (in RULE1) depends on $(DO_ALSO). -For normal configurations, DO_ALSO=needed-list. - -So needed-list is first made. The needed-list rule compiles -dummy.c. Because dummy.c includes functions.def, the -resulting object file will contain a call to each of the -optional functions (for simplicity assume each optional file -defines a single function). This object file will be linked -against the standard libraries (as defined by using $(CC) -and various flags). Any function missing will causes the -linker to emit an error message. We assume the name -of the missing function(s) are in the error message(s). -The awk script find-needed.awk has been generated from -functions.def. It is used to search the linker output -messages for words that match the functions listed in -functions.def. The list of functions found is written -on a single line to the file needed-list. - -After needed-list has been generated, the libiberty.a -target (in RULE1) just calls 'make' recursively. -It passes the contents of needed-list using the -definition (expanded) HOST_OFILES="`cat needed-list`". -It also tells the inferior 'make' to use RULE2. - -The inferior 'make' is very conventional: The main -rule is $(RULE2) (which is libiberty.a). It depends -on a list of object files: $(REQUIRED_OFILES) $(HOST_OFILES) -(and $(EXTRA_OFILES), which is usually empty). The superior -'make' passes in $(HOST_OFILES); the others are fixed -in the Makefile. - -ADDING A NEW CONFIGURATION -========================== - -On most hosts you should be able to use the scheme for automatically -figuring out which files are needed. In that case, you probably -don't need a special Makefile stub for that configuration. - -If the fully automatic scheme doesn't work, you may be able to get -by with defining EXTRA_OFILES in your Makefile stub. This is -a list of object file names that should be treated as required -for this configuration - they will be included in libiberty.a, -regardless of whatever might be in the C library. Moreover, -when the dummy.c program is linked, it will be linked with -$(EXTRA_OFILES). Therefore, if a function in functions.def -is defined by one of the EXTRA_OFILES, it will not be listed as -"needed". Thus if your hal9000 host needs a special implementation -of getcwd, you can just create hal9000-getcwd.c, and define: - EXTRA_OFILES=hal9000-getcwd.o -Or if you want to use the libiberty version of strstr(), -even though there is a version in the C library (it might be -buggy or slow), just define: - EXTRA_OFILES=strstr.o - -You can create a "manual" host configuration FOO with a file -config/mh-FOO. In it, the HOST_OFILES macro should explicitly -list that subset of the optional files that should be in the -library. You should also set: - DO_ALSO = -This overrides all of the magic needed to automatically -determine which files are "needed." However, keeping that list -up to date is another matter... - -HOW THE MANUAL CONFIGURATION WORKS -================================== - -This also uses a recursive make, but the superior make -does not do anything interesting - it just calls the -inferior make with HOST_OFILES defined as $(HOST_OFILES), -which is the list you created in your configuration. - -You probably don't want to depend on manual configuration, -because keeping the HOST_OFILES list up-to-date will be a pain. |