libctf: don't run tests requiring deduplicating linker unless one is in use Before now, we were relying on gcc -B to repoint GCC at our freshly-built linker, and assuming we could use this to run tests that do linker dedup. This is, alas, not reliable (building --with-ld=/an/absolute/path bypasses -B searches for the linker), and we would like the libctf tests in particular to not fail if the compiler uses a linker that cannot deduplicate (simply skipping such tests). Add a new testsuite function that tries to link one of the lookup tests' testcases (which is known to produce conflicting types, i.e. a dict with per-translation-unit children) and then does an objdump and greps it for signs of the per-translation-unit children. If there are none, the linker probably just concatenated the sections: i.e., it is not a linker that can deduplicate CTF. libctf/ PR libctf/33162 * testsuite/config/default.exp (objdump): Introduce. (OBJDUMPFLAGS): Likewise. * testsuite/lib/ctf-lib.exp (check_ctf_linker_dedup): New. * testsuite/libctf-lookup/lookup.exp: Use it. * testsuite/libctf-regression/libctf-repeat-cu.exp: Likewise. * testsuite/libctf-regression/regression.exp: Likewise.
diff --git a/libctf/testsuite/config/default.exp b/libctf/testsuite/config/default.exp index f244826..d5e51f4 100644 --- a/libctf/testsuite/config/default.exp +++ b/libctf/testsuite/config/default.exp
@@ -34,6 +34,10 @@ set as [findfile $base_dir/../gas/as-new $base_dir/../gas/as-new [transform as]] } +if ![info exists objdump] then { + set objdump [findfile $base_dir/../binutils/objdump] +} + remote_exec host "mkdir -p tmpdir" # Make symlinks from tmpdir/libctf to the linker and assembler in the @@ -63,10 +67,12 @@ if ![info exists AR] then { set AR [findfile $base_dir/../binutils/ar] } - if {![info exists OBJDUMP]} { set OBJDUMP [findfile $base_dir/../binutils/objdump] } +if ![info exists OBJDUMPFLAGS] then { + set OBJDUMPFLAGS {} +} # load the utility procedures load_lib ctf-lib.exp
diff --git a/libctf/testsuite/lib/ctf-lib.exp b/libctf/testsuite/lib/ctf-lib.exp index 64d2a40..4df6619 100644 --- a/libctf/testsuite/lib/ctf-lib.exp +++ b/libctf/testsuite/lib/ctf-lib.exp
@@ -20,6 +20,51 @@ load_file $srcdir/../../ld/testsuite/lib/ld-lib.exp +# Returns true if the target linker deduplicates CTF. +proc check_ctf_linker_dedup { } { + global ctf_linker_dedup_saved + + if {![info exists ctf_linker_dedup_saved]} { + set ctf_linker_dedup_saved 0 + + if ([check_ctf_available]) { + global objdump srcdir + + set basename "tmpdir/ctf_linker_dedups[pid]" + compile_one_cc $srcdir/libctf-lookup/ambiguous-struct-A.c ${basename}-A.o "-gctf -fPIC -c" + compile_one_cc $srcdir/libctf-lookup/ambiguous-struct-B.c ${basename}-B.o "-gctf -fPIC -c" + compile_one_cc "${basename}-A.o ${basename}-B.o" $basename.so "-gctf -fPIC -shared" + if {! [remote_file host exists $basename.so] } { + return 0 + } + + # Don't use run_host_cmd: it dumps the entire output into the log, + # even on success. + set cmdret [remote_exec host [concat sh -c [list "$objdump --ctf $basename.so >dump.out 2>dump.err"]] "" "/dev/null"] + set cmdret [lindex $cmdret 0] + remote_upload host "dump.out" + remote_upload host "dump.err" + set dump_out [prune_warnings [file_contents "dump.out"]] + set dump_err [prune_warnings [file_contents "dump.err"]] + remote_file host delete "dump.out" "dump.err" + remote_file build delete "dump.out" "dump.err" + + if {$cmdret != 0} { + verbose -log "failed with $cmdret: stderr: $dump_err" + verbose -log "output: $dump_out" + return 0; + } + + remote_file host delete $basename.so ${basename}-A.o ${basename}-B.o + if [regexp {CTF archive member: } $dump_out] { + set ctf_linker_dedup_saved 1 + } + } + } + return $ctf_linker_dedup_saved +} + + proc run_native_host_cmd { command } { global link_output global ld
diff --git a/libctf/testsuite/libctf-lookup/lookup.exp b/libctf/testsuite/libctf-lookup/lookup.exp index a8b09c2..d15c315 100644 --- a/libctf/testsuite/libctf-lookup/lookup.exp +++ b/libctf/testsuite/libctf-lookup/lookup.exp
@@ -28,6 +28,11 @@ return 0 } +if {![check_ctf_linker_dedup]} { + unsupported "no CTF deduplication support in the linker" + return 0 +} + if {[info exists env(LC_ALL)]} { set old_lc_all $env(LC_ALL) }
diff --git a/libctf/testsuite/libctf-regression/libctf-repeat-cu.exp b/libctf/testsuite/libctf-regression/libctf-repeat-cu.exp index e29cf63..7c19fe8 100644 --- a/libctf/testsuite/libctf-regression/libctf-repeat-cu.exp +++ b/libctf/testsuite/libctf-regression/libctf-repeat-cu.exp
@@ -37,6 +37,11 @@ return 0 } +if {![check_ctf_linker_dedup]} { + unsupported "no CTF deduplication support in the linker" + return 0 +} + if {[info exists env(LC_ALL)]} { set old_lc_all $env(LC_ALL) }
diff --git a/libctf/testsuite/libctf-regression/regression.exp b/libctf/testsuite/libctf-regression/regression.exp index e4b6347..0270cca 100644 --- a/libctf/testsuite/libctf-regression/regression.exp +++ b/libctf/testsuite/libctf-regression/regression.exp
@@ -23,6 +23,11 @@ return 0 } +if {![check_ctf_linker_dedup]} { + unsupported "no CTF deduplication support in the linker" + return 0 +} + if ![is_elf_format] { unsupported "CTF needs bfd changes to be emitted on non-ELF" return 0