[PATCH v1] tools build: Fix a number of Wconversion warnings

[Ian Rogers]

There's some expressed interest in having the compiler flag
-Wconversion detect at build time certain kinds of potential problems:
https://lore.kernel.org/lkml/20250103182532.GB781381@xxxxxxxxxxxxxxx/

As feature detection passes -Wconversion from CFLAGS when set, the
feature detection compile tests need to not fail because of
-Wconversion as the failure will be interpretted as a missing
feature. Switch various types to avoid the -Wconversion issue, the
exact meaning of the code is unimportant as it is typically looking
for header file definitions.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
 tools/build/feature/test-backtrace.c           | 2 +-
 tools/build/feature/test-bpf.c                 | 2 +-
 tools/build/feature/test-glibc.c               | 2 +-
 tools/build/feature/test-libdebuginfod.c       | 2 +-
 tools/build/feature/test-libdw.c               | 2 +-
 tools/build/feature/test-libelf-gelf_getnote.c | 2 +-
 tools/build/feature/test-libelf.c              | 2 +-
 tools/build/feature/test-lzma.c                | 2 +-
 8 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/build/feature/test-backtrace.c b/tools/build/feature/test-backtrace.c
index e9ddd27c69c3..7962fbad6401 100644
--- a/tools/build/feature/test-backtrace.c
+++ b/tools/build/feature/test-backtrace.c
@@ -5,7 +5,7 @@
 int main(void)
 {
 	void *backtrace_fns[10];
-	size_t entries;
+	int entries;
 
 	entries = backtrace(backtrace_fns, 10);
 	backtrace_symbols_fd(backtrace_fns, entries, 1);
diff --git a/tools/build/feature/test-bpf.c b/tools/build/feature/test-bpf.c
index 727d22e34a6e..e7a405f83af6 100644
--- a/tools/build/feature/test-bpf.c
+++ b/tools/build/feature/test-bpf.c
@@ -44,5 +44,5 @@ int main(void)
 	 * Test existence of __NR_bpf and BPF_PROG_LOAD.
 	 * This call should fail if we run the testcase.
 	 */
-	return syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
+	return syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr)) == 0;
 }
diff --git a/tools/build/feature/test-glibc.c b/tools/build/feature/test-glibc.c
index 9ab8e90e7b88..20a250419f31 100644
--- a/tools/build/feature/test-glibc.c
+++ b/tools/build/feature/test-glibc.c
@@ -16,5 +16,5 @@ int main(void)
 	const char *version = XSTR(__GLIBC__) "." XSTR(__GLIBC_MINOR__);
 #endif
 
-	return (long)version;
+	return version == NULL;
 }
diff --git a/tools/build/feature/test-libdebuginfod.c b/tools/build/feature/test-libdebuginfod.c
index da22548b8413..823f9fa9391d 100644
--- a/tools/build/feature/test-libdebuginfod.c
+++ b/tools/build/feature/test-libdebuginfod.c
@@ -4,5 +4,5 @@
 int main(void)
 {
 	debuginfod_client* c = debuginfod_begin();
-	return (long)c;
+	return !!c;
 }
diff --git a/tools/build/feature/test-libdw.c b/tools/build/feature/test-libdw.c
index 2fb59479ab77..aabd63ca76b4 100644
--- a/tools/build/feature/test-libdw.c
+++ b/tools/build/feature/test-libdw.c
@@ -9,7 +9,7 @@ int test_libdw(void)
 {
 	Dwarf *dbg = dwarf_begin(0, DWARF_C_READ);
 
-	return (long)dbg;
+	return dbg == NULL;
 }
 
 int test_libdw_unwind(void)
diff --git a/tools/build/feature/test-libelf-gelf_getnote.c b/tools/build/feature/test-libelf-gelf_getnote.c
index 075d062fe841..e06121161161 100644
--- a/tools/build/feature/test-libelf-gelf_getnote.c
+++ b/tools/build/feature/test-libelf-gelf_getnote.c
@@ -4,5 +4,5 @@
 
 int main(void)
 {
-	return gelf_getnote(NULL, 0, NULL, NULL, NULL);
+	return gelf_getnote(NULL, 0, NULL, NULL, NULL) == 0;
 }
diff --git a/tools/build/feature/test-libelf.c b/tools/build/feature/test-libelf.c
index 905044127d56..2dbb6ea870f3 100644
--- a/tools/build/feature/test-libelf.c
+++ b/tools/build/feature/test-libelf.c
@@ -5,5 +5,5 @@ int main(void)
 {
 	Elf *elf = elf_begin(0, ELF_C_READ, 0);
 
-	return (long)elf;
+	return !!elf;
 }
diff --git a/tools/build/feature/test-lzma.c b/tools/build/feature/test-lzma.c
index 78682bb01d57..b57103774e8e 100644
--- a/tools/build/feature/test-lzma.c
+++ b/tools/build/feature/test-lzma.c
@@ -4,7 +4,7 @@
 int main(void)
 {
 	lzma_stream strm = LZMA_STREAM_INIT;
-	int ret;
+	lzma_ret ret;
 
 	ret = lzma_stream_decoder(&strm, UINT64_MAX, LZMA_CONCATENATED);
 	return ret ? -1 : 0;
-- 
2.47.1.613.gc27f4b7a9f-goog