[binutils-gdb] [gdb/testsuite] Fix "unable to find usable gdb" error with cc-with-tweaks.exp

[binutils-gdb] [gdb/testsuite] Fix "unable to find usable gdb" error with cc-with-tweaks.exp

[Tom de Vries]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f59f30f55776b10d4f728065e9f9a10cf63a1b29

commit f59f30f55776b10d4f728065e9f9a10cf63a1b29
Author: Tom de Vries <tdevries@suse.de>
Date:   Wed May 1 15:31:14 2019 +0200

    [gdb/testsuite] Fix "unable to find usable gdb" error with cc-with-tweaks.exp
    
    When running fullpath-expand.exp with target_board=dwarf4-gdb-index, we run
    into:
    ...
    $ make check-gdb RUNTESTFLAGS="--target_board=dwarf4-gdb-index fullpath-expand.exp"
    Running src/gdb/testsuite/gdb.base/fullpath-expand.exp ...
    gdb compile failed, cc-with-tweaks.sh: unable to find usable gdb
    
                    === gdb Summary ===
    
    nr of untested testcases         1
    ...
    The same happens with fullname.exp.
    
    The dwarf4-gdb-index.exp board file includes cc-with-tweaks.exp, which uses
    cc-with-tweaks.sh, which calls gdb-add-index.sh.
    
    The gdb-add-index.sh script uses a gdb executable, defaulting to gdb:
    ...
    GDB=${GDB:=gdb}
    ...
    
    The cc-with-tweaks.sh script tries to ensure that the build gdb executable is
    used by gdb-add-index.sh:
    ...
    if [ -z "$GDB" ]
    then
        if [ -f ./gdb ]
        then
    	GDB="./gdb -data-directory data-directory"
        elif [ -f ../gdb ]
        then
    	GDB="../gdb -data-directory ../data-directory"
        elif [ -f ../../gdb ]
        then
    	GDB="../../gdb -data-directory ../../data-directory"
        else
    	echo "$myname: unable to find usable gdb" >&2
    	exit 1
        fi
    fi
    ...
    So, if the current directory is build/gdb/testsuite, then a gdb executable
    build/gdb/testsuite/../gdb will be used.
    
    However, in the case of fullpath-expand.exp the test cd's into the sources:
    ...
    set saved_pwd [pwd]
    cd $srcdir
    set err [gdb_compile "${subdir}/${srcfile} ${subdir}/${srcfile2}" $binfile \
             executable {debug}]
    cd $saved_pwd
    ...
    and cc-with-tweaks.sh generates the "unable to find usable gdb" error.
    
    The same error occurs if we use --target_board=cc-with-dwz instead (only in
    this case we actually don't need gdb, we just need the GDB variable to be set
    in cc-with-tweaks.sh, which arguably is a bug in cc-with-tweaks.sh).
    
    Fix both errors in cc-with-tweaks.exp by generating a gdb script gdb.sh using
    $GDB, $GDBFLAGS and $INTERNAL_GDBFLAGS and passing this script to
    cc-with-tweaks.sh by setting env(GDB).
    
    Tested on x86_64-linux for gdb.base.
    
    gdb/testsuite/ChangeLog:
    
    2019-05-01  Tom de Vries  <tdevries@suse.de>
    
    	* boards/cc-with-tweaks.exp: Generate gdb.sh, and pass it in env(GDB).

Diff:
---
 gdb/testsuite/ChangeLog                 | 4 ++++
 gdb/testsuite/boards/cc-with-tweaks.exp | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index e1c2bfa..6331e52 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,9 @@
 2019-05-01  Tom de Vries  <tdevries@suse.de>
 
+	* boards/cc-with-tweaks.exp: Generate gdb.sh, and pass it in env(GDB).
+
+2019-05-01  Tom de Vries  <tdevries@suse.de>
+
 	* boards/dwarf4-gdb-index.exp: Use cc-with-tweaks.exp.
 
 2019-04-30  Ali Tamur  <tamur@google.com>
diff --git a/gdb/testsuite/boards/cc-with-tweaks.exp b/gdb/testsuite/boards/cc-with-tweaks.exp
index 11ec6a2..c50a006 100644
--- a/gdb/testsuite/boards/cc-with-tweaks.exp
+++ b/gdb/testsuite/boards/cc-with-tweaks.exp
@@ -53,3 +53,8 @@ if ![info exists CXX_FOR_TARGET] {
     set CXX_FOR_TARGET "$found_gxx"
 }
 set CXX_FOR_TARGET "$contrib_dir/cc-with-tweaks.sh $CC_WITH_TWEAKS_FLAGS $CXX_FOR_TARGET"
+
+set pwd [exec pwd -P]
+exec echo $GDB $INTERNAL_GDBFLAGS $GDBFLAGS \"\$@\" > $pwd/gdb.sh
+exec chmod +x gdb.sh
+set env(GDB) $pwd/gdb.sh