src: rework mem_clear()

src/compress/compress.cpp

@@ -83,7 +83,7 @@ int upx_compress(const upx_bytep src, unsigned src_len, upx_bytep dst, unsigned
 
     if (!cresult)
         cresult = &cresult_buffer;
-    memset(cresult, 0, sizeof(*cresult));
+    cresult->reset();
 #if 1
     // debugging aid
     cresult->debug.method = method;

src/compress/compress_lzma.cpp

@@ -433,7 +433,7 @@ int upx_lzma_decompress(const upx_bytep src, unsigned src_len, upx_bytep dst, un
     COMPILE_TIME_ASSERT(LZMA_LIT_SIZE == 768)
 
     CLzmaDecoderState s;
-    memset(&s, 0, sizeof(s));
+    mem_clear(&s);
     SizeT src_out = 0, dst_out = 0;
     int r = UPX_E_ERROR;
     int rh;

src/compress/compress_zlib.cpp

@@ -31,8 +31,7 @@
 #include <zlib/deflate.h>
 
 void zlib_compress_config_t::reset() noexcept {
-    mem_clear(this, sizeof(*this));
-
+    mem_clear(this);
     mem_level.reset();
     window_bits.reset();
     strategy.reset();

src/compress/compress_zstd.cpp

@@ -26,7 +26,7 @@
 
 #include "../conf.h"
 
-void zstd_compress_config_t::reset() noexcept { mem_clear(this, sizeof(*this)); }
+void zstd_compress_config_t::reset() noexcept { mem_clear(this); }
 
 #if WITH_ZSTD
 #include "compress.h"