Create two .o files containing BTF as a result of passing -gbtf
and ensure that we can run BTF generation (and dedup) on them
to get a valid detached BTF output.
Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
---
tests/btf_2_btf.sh | 122 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 122 insertions(+)
create mode 100755 tests/btf_2_btf.sh
diff --git a/tests/btf_2_btf.sh b/tests/btf_2_btf.sh
new file mode 100755
index 0000000..dbc4f34
--- /dev/null
+++ b/tests/btf_2_btf.sh
@@ -0,0 +1,122 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (c) 2025, Oracle and/or its affiliates.
+#
+# Use -gbtf to compile objects with BTF and combine/dedup the
+# BTF using pahole; this tests the ability to take BTF as
+# input for BTF encoding as well as DWARF.
+#
+
+outdir=
+
+fail()
+{
+ # Do not remove test dir; might be useful for analysis
+ trap - EXIT
+ if [[ -d "$outdir" ]]; then
+ echo "Test data is in $outdir"
+ fi
+ exit 1
+}
+
+cleanup()
+{
+ rm ${outdir}/*
+ rmdir $outdir
+}
+
+outdir=$(mktemp -d /tmp/btf_2_btf.sh.XXXXXX)
+
+trap cleanup EXIT
+
+echo -n "Validation of BTF encoding from cc-generated BTF: "
+
+cat <<EOF > ${outdir}/f1.c
+#include <stdlib.h>
+
+enum foo {
+ E1,
+ E2,
+ E3
+};
+
+struct bar {
+ enum foo f1;
+ int f2;
+ char *f3;
+ void *f4;
+};
+
+int baz(struct bar *b)
+{
+ return b->f2++;
+}
+EOF
+gcc -gbtf -c ${outdir}/f1.c -o ${outdir}/f1.o
+if [[ $? -ne 0 ]]; then
+ echo "skip: -gbtf not supported or gcc not present"
+ exit 1
+fi
+
+cat <<EOF > ${outdir}/f2.c
+#include <stdlib.h>
+
+enum foo {
+ E1,
+ E2,
+ E3
+};
+
+struct bar {
+ enum foo f1;
+ int f2;
+ char *f3;
+ void *f4;
+};
+
+struct bar2 {
+ void *f1;
+ int f2[3];
+};
+
+int othervar;
+
+void *baz2(struct bar2 *b2, char *o)
+{
+ if (b2->f2[0] > 2)
+ return NULL;
+ return o;
+}
+EOF
+gcc -gbtf -c ${outdir}/f2.c -o ${outdir}/f2.o
+
+pahole -J --format_path=btf --btf_features=default --lang_exclude=rust \
+ --btf_encode_detached=${outdir}/cc.btf ${outdir}/f1.o ${outdir}/f2.o
+
+for f in ${outdir}/f1.o ${outdir}/cc.btf ; do
+ struct=$(pahole $f |grep "struct bar" 2>/dev/null)
+ if [[ -z "$struct" ]]; then
+ echo "struct bar not found in '$f'"
+ fail
+ fi
+ fns=$(pfunct --all $f |grep baz 2>/dev/null)
+ if [[ -z "$fns" ]]; then
+ echo "function baz not found in '$f'"
+ fail
+ fi
+done
+struct=$(pahole $f |grep "struct bar2" 2>/dev/null)
+if [[ -z "$struct" ]]; then
+ echo "struct bar2 not found in '$f'"
+ fail
+fi
+fn=$(pfunct --all $f |grep "baz2" 2>/dev/null)
+if [[ -z "$fn" ]]; then
+ echo "function baz2 not found in '$f'"
+ fail
+fi
+
+echo "Ok"
+
+exit 0
--
2.43.5
