From 8e514c5cb64dc88350ded69e2e9e60b546457434 Mon Sep 17 00:00:00 2001
From: Sergey B Kirpichev <skirpichev@gmail.com>
Date: Tue, 30 Jan 2024 15:54:39 +0300
Subject: [PATCH] gh-108562: fix compiler warnings for bundled libmpdec in the
 main

This patch enable (if awailable) -fstrict-overflow for libmpdec and also
shut off false positive warnings (-Warray-bounds).  The later part
was backported from mpdecimal-4.0.0.
---
 Makefile.pre.in                | 2 +-
 Misc/sbom.spdx.json            | 4 ++--
 Modules/_decimal/libmpdec/io.c | 1 +
 configure                      | 7 +++++++
 configure.ac                   | 5 +++++
 5 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/Makefile.pre.in b/Makefile.pre.in
index 37a8b06987c710..1b805141f4412d 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -937,7 +937,7 @@ python.worker.js: $(srcdir)/Tools/wasm/python.worker.js
 
 ##########################################################################
 # Build static libmpdec.a
-LIBMPDEC_CFLAGS=@LIBMPDEC_CFLAGS@ $(PY_STDMODULE_CFLAGS) $(CCSHARED)
+LIBMPDEC_CFLAGS=$(PY_STDMODULE_CFLAGS) @LIBMPDEC_CFLAGS@ $(CCSHARED)
 
 # "%.o: %c" is not portable
 Modules/_decimal/libmpdec/basearith.o: $(srcdir)/Modules/_decimal/libmpdec/basearith.c $(LIBMPDEC_HEADERS) $(PYTHON_HEADERS)
diff --git a/Misc/sbom.spdx.json b/Misc/sbom.spdx.json
index 94566772338b10..e8f415df4eeaaf 100644
--- a/Misc/sbom.spdx.json
+++ b/Misc/sbom.spdx.json
@@ -1238,11 +1238,11 @@
       "checksums": [
         {
           "algorithm": "SHA1",
-          "checksumValue": "12402bcf7f0161adb83f78163f41cc10a5e5de5f"
+          "checksumValue": "9dcb50e3f9c3245972731be5da0b28e7583198d9"
         },
         {
           "algorithm": "SHA256",
-          "checksumValue": "cba044c76b6bc3ae6cfa49df1121cad7552140157b9e61e11cbb6580cc5d74cf"
+          "checksumValue": "7cac49fef5e9d952ec9390bf81c54d83f1b5da32fdf76091c2f0770ed943b7fe"
         }
       ],
       "fileName": "Modules/_decimal/libmpdec/io.c"
diff --git a/Modules/_decimal/libmpdec/io.c b/Modules/_decimal/libmpdec/io.c
index e7bd6aee170056..4e95b8964c8e5d 100644
--- a/Modules/_decimal/libmpdec/io.c
+++ b/Modules/_decimal/libmpdec/io.c
@@ -48,6 +48,7 @@
 #if defined(__GNUC__) && !defined(__INTEL_COMPILER) && __GNUC__ >= 7
   #pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
   #pragma GCC diagnostic ignored "-Wmisleading-indentation"
+  #pragma GCC diagnostic ignored "-Warray-bounds"
 #endif
 
 
diff --git a/configure b/configure
index b1153df4d7ec52..3df6135a1aeedc 100755
--- a/configure
+++ b/configure
@@ -14359,6 +14359,13 @@ else $as_nop
   LIBMPDEC_LDFLAGS="-lm \$(LIBMPDEC_A)"
   LIBMPDEC_INTERNAL="\$(LIBMPDEC_HEADERS) \$(LIBMPDEC_A)"
 
+    if test "x$ac_cv_cc_supports_fstrict_overflow" = xyes
+then :
+
+    as_fn_append LIBMPDEC_CFLAGS " -fstrict-overflow"
+
+fi
+
     if test "x$with_pydebug" = xyes
 then :
 
diff --git a/configure.ac b/configure.ac
index 9587e6d63499aa..d18913f12c7297 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3744,6 +3744,11 @@ AS_VAR_IF([with_system_libmpdec], [yes], [
   LIBMPDEC_LDFLAGS="-lm \$(LIBMPDEC_A)"
   LIBMPDEC_INTERNAL="\$(LIBMPDEC_HEADERS) \$(LIBMPDEC_A)"
 
+  dnl Enable strict-overflow for libmpdec, if available, see GH-108562
+  AS_VAR_IF([ac_cv_cc_supports_fstrict_overflow], [yes], [
+    AS_VAR_APPEND([LIBMPDEC_CFLAGS], [" -fstrict-overflow"])
+  ])
+
   dnl Disable forced inlining in debug builds, see GH-94847
   AS_VAR_IF([with_pydebug], [yes], [
     AS_VAR_APPEND([LIBMPDEC_CFLAGS], [" -DTEST_COVERAGE"])