From 8163aa935e9dcbc15c6c091da7fc42f017fc7ce9 Mon Sep 17 00:00:00 2001
From: Matthew Smith
Date: Mon, 25 Jul 2022 19:06:41 +0100
Subject: bplist: Fix strict aliasing violations

Casting a float pointer to an int pointer is a strict aliasing
violation (-Wstrict-aliasing) and is undefined behaviour (although, it
did not seem to cause any real issues).

An optimising compiler should elide the memcopies added by this commit.
---
 src/bplist.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/bplist.c b/src/bplist.c
index 57ec151..c8f5ebc 100644
--- a/src/bplist.c
+++ b/src/bplist.c
@@ -998,18 +998,24 @@ static void write_real(bytearray_t * bplist, double val)
     buff[7] = BPLIST_REAL | Log2(size);
     if (size == sizeof(float)) {
         float floatval = (float)val;
-        *(uint32_t*)(buff+8) = float_bswap32(*(uint32_t*)&floatval);
+        uint32_t intval;
+        memcpy(&intval, &floatval, sizeof(float));
+        *(uint32_t*)(buff+8) = float_bswap32(intval);
     } else {
-        *(uint64_t*)(buff+8) = float_bswap64(*(uint64_t*)&val);
+        uint64_t intval;
+        memcpy(&intval, &val, sizeof(double));
+        *(uint64_t*)(buff+8) = float_bswap64(intval);
     }
     byte_array_append(bplist, buff+7, size+1);
 }
 
 static void write_date(bytearray_t * bplist, double val)
 {
+    uint64_t intval;
+    memcpy(&intval, &val, sizeof(double));
     uint8_t buff[16];
     buff[7] = BPLIST_DATE | 3;
-    *(uint64_t*)(buff+8) = float_bswap64(*(uint64_t*)&val);
+    *(uint64_t*)(buff+8) = float_bswap64(intval);
     byte_array_append(bplist, buff+7, 9);
 }
 
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