From 22bca4a14f5be84b63ce53745dfb0df7e4b822d5 Mon Sep 17 00:00:00 2001
From: Matt Coster <matt.coster@imgtec.com>
Date: Wed, 20 Sep 2023 16:00:19 +0100
Subject: [PATCH] pvr: Force compile error on GNU void pointer arithmetic

This GNU extension caused a bug where a void pointer was modified then
interpreted as uint32_t* (instead of the other way round). Force a
compile error to (hopefully) prevent this from happening again.

Signed-off-by: Matt Coster <matt.coster@imgtec.com>
Reviewed-by: Karmjit Mahil <Karmjit.Mahil@imgtec.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25327>
---
 src/imagination/common/meson.build      | 2 +-
 src/imagination/meson.build             | 4 ++++
 src/imagination/rogue/meson.build       | 2 +-
 src/imagination/rogue/tools/meson.build | 1 +
 src/imagination/vulkan/meson.build      | 1 +
 src/imagination/vulkan/pds/meson.build  | 1 +
 6 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/imagination/common/meson.build b/src/imagination/common/meson.build
index 96609549f8e..023dd9495dc 100644
--- a/src/imagination/common/meson.build
+++ b/src/imagination/common/meson.build
@@ -34,6 +34,6 @@ libpowervr_common = static_library(
     inc_src,
     inc_imagination,
   ],
-  c_args : [no_override_init_args],
+  c_args : [imagination_c_args, no_override_init_args],
   gnu_symbol_visibility : 'hidden',
 )
diff --git a/src/imagination/meson.build b/src/imagination/meson.build
index 626a03a3d76..0bb2401ff4e 100644
--- a/src/imagination/meson.build
+++ b/src/imagination/meson.build
@@ -19,6 +19,10 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+imagination_c_args = cc.get_supported_arguments(
+  '-Werror=pointer-arith',
+)
+
 inc_imagination = include_directories([
   '.',
   'common',
diff --git a/src/imagination/rogue/meson.build b/src/imagination/rogue/meson.build
index d7b06bb6ce7..120de6b3233 100644
--- a/src/imagination/rogue/meson.build
+++ b/src/imagination/rogue/meson.build
@@ -63,7 +63,7 @@ libpowervr_rogue = shared_library(
     inc_include,
     inc_src,
   ],
-  c_args : [no_override_init_args],
+  c_args : [imagination_c_args, no_override_init_args],
   gnu_symbol_visibility : 'hidden',
   dependencies : [idep_mesautil, idep_nir, idep_vulkan_runtime, dep_csbgen],
   install : true,
diff --git a/src/imagination/rogue/tools/meson.build b/src/imagination/rogue/tools/meson.build
index 1eb55bb4629..6158615278c 100644
--- a/src/imagination/rogue/tools/meson.build
+++ b/src/imagination/rogue/tools/meson.build
@@ -32,6 +32,7 @@ rogue_compiler = executable(
     inc_src,
     inc_rogue,
   ],
+  c_args : [imagination_c_args],
   build_by_default : with_imagination_tools,
   install : false,
 )
diff --git a/src/imagination/vulkan/meson.build b/src/imagination/vulkan/meson.build
index bfe8def182e..b3c88065d96 100644
--- a/src/imagination/vulkan/meson.build
+++ b/src/imagination/vulkan/meson.build
@@ -91,6 +91,7 @@ pvr_deps = [
 ]
 
 pvr_flags = [
+  imagination_c_args,
   no_override_init_args,
 ]
 
diff --git a/src/imagination/vulkan/pds/meson.build b/src/imagination/vulkan/pds/meson.build
index b115d2da541..6685dc1cda1 100644
--- a/src/imagination/vulkan/pds/meson.build
+++ b/src/imagination/vulkan/pds/meson.build
@@ -43,6 +43,7 @@ libpowervr_pds = static_library(
     inc_imagination,
   ],
   c_args : [
+    imagination_c_args,
     no_override_init_args,
   ],
   gnu_symbol_visibility : 'hidden',