This patch unifies the handling of zero capacity regions for structs
and other types in the allocation size checker.
Regression-tested on x86_64 Linux.
2022-07-22 Tim Lange
gcc/analyzer/ChangeLog:
PR analyzer/106394
* region-model.cc (capacity_compatible_with_type): Always return true
if alloc_size is zero.
gcc/testsuite/ChangeLog:
PR analyzer/106394
* gcc.dg/analyzer/pr106394.c: New test.
---
gcc/analyzer/region-model.cc | 2 +-
gcc/testsuite/gcc.dg/analyzer/pr106394.c | 19 +++
2 files changed, 20 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/analyzer/pr106394.c
diff --git a/gcc/analyzer/region-model.cc b/gcc/analyzer/region-model.cc
index 8b7b4e1f697..e01c30407c4 100644
--- a/gcc/analyzer/region-model.cc
+++ b/gcc/analyzer/region-model.cc
@@ -2956,7 +2956,7 @@ capacity_compatible_with_type (tree cst, tree
pointee_size_tree,
unsigned HOST_WIDE_INT alloc_size = TREE_INT_CST_LOW (cst);
if (is_struct)
-return alloc_size >= pointee_size;
+return alloc_size == 0 || alloc_size >= pointee_size;
return alloc_size % pointee_size == 0;
}
diff --git a/gcc/testsuite/gcc.dg/analyzer/pr106394.c
b/gcc/testsuite/gcc.dg/analyzer/pr106394.c
new file mode 100644
index 000..96bb175fc14
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/analyzer/pr106394.c
@@ -0,0 +1,19 @@
+struct msm_gpu {
+ // [...snip...]
+ const struct msm_gpu_perfcntr *perfcntrs;
+ // [...snip...]
+};
+
+struct msm_gpu_perfcntr {
+ // [...snip...]
+ const char *name;
+};
+
+static const struct msm_gpu_perfcntr perfcntrs[] = {};
+
+struct msm_gpu *test(struct msm_gpu *gpu) {
+ // [...snip...]
+ gpu->perfcntrs = perfcntrs;
+ // [...snip...]
+ return gpu;
+}
--
2.36.1