Apply patch from Remi Collet: za can be NULL.

lib/zip_fclose.c

diff --git a/lib/zip_fclose.c b/lib/zip_fclose.c
index f25b58c..c05ec3d 100644
--- a/lib/zip_fclose.c
+++ b/lib/zip_fclose.c
@@ -48,12 +48,14 @@
     if (zf->src)
 	zip_source_free(zf->src);
 
-    for (i=0; i<zf->za->nfile; i++) {
-	if (zf->za->file[i] == zf) {
-	    zf->za->file[i] = zf->za->file[zf->za->nfile-1];
-	    zf->za->nfile--;
-	    break;
-	}
+    if (zf->za) {
+        for (i=0; i<zf->za->nfile; i++) {
+            if (zf->za->file[i] == zf) {
+                zf->za->file[i] = zf->za->file[zf->za->nfile-1];
+                zf->za->nfile--;
+                break;
+            }
+        }
     }
 
     ret = 0;

xcode/libzip.xcodeproj/project.pbxproj

diff --git a/xcode/libzip.xcodeproj/project.pbxproj b/xcode/libzip.xcodeproj/project.pbxproj
index 9371cda..9db94f4 100644
--- a/xcode/libzip.xcodeproj/project.pbxproj
+++ b/xcode/libzip.xcodeproj/project.pbxproj
@@ -1643,7 +1643,7 @@
 		4BDC71BF15B181DA00236D3C /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 0460;
+				LastUpgradeCheck = 0500;
 				ORGANIZATIONNAME = "Spider Lab";
 			};
 			buildConfigurationList = 4BDC71C215B181DA00236D3C /* Build configuration list for PBXProject "libzip" */;
@@ -2715,9 +2715,10 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
-				ARCHS = "$(ARCHS_STANDARD_32_64_BIT)";
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
@@ -2731,8 +2732,11 @@
 				);
 				GCC_SYMBOLS_PRIVATE_EXTERN = NO;
 				GCC_VERSION = com.apple.compilers.llvm.clang.1_0;
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
 				GCC_WARN_ABOUT_RETURN_TYPE = YES;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
 				GCC_WARN_UNINITIALIZED_AUTOS = YES;
+				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 5.1;
 				MACOSX_DEPLOYMENT_TARGET = 10.6;
@@ -2745,17 +2749,21 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
-				ARCHS = "$(ARCHS_STANDARD_32_64_BIT)";
 				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
 				CLANG_WARN_ENUM_CONVERSION = YES;
 				CLANG_WARN_INT_CONVERSION = YES;
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				COPY_PHASE_STRIP = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_VERSION = com.apple.compilers.llvm.clang.1_0;
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
 				GCC_WARN_ABOUT_RETURN_TYPE = YES;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
 				GCC_WARN_UNINITIALIZED_AUTOS = YES;
+				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 5.1;
 				MACOSX_DEPLOYMENT_TARGET = 10.6;
@@ -2767,11 +2775,6 @@
 		4BDC71EB15B182B200236D3C /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				ARCHS = (
-					"$(ARCHS_STANDARD_64_BIT)",
-					"$(ARCHI_STANDARD_32_BIT)",
-					armv7,
-				);
 				CLANG_WARN_SUSPICIOUS_IMPLICIT_CONVERSION = YES;
 				COPY_PHASE_STRIP = YES;
 				GCC_C_LANGUAGE_STANDARD = c99;
@@ -2794,11 +2797,6 @@
 		4BDC71EC15B182B200236D3C /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				ARCHS = (
-					"$(ARCHS_STANDARD_64_BIT)",
-					"$(ARCHI_STANDARD_32_BIT)",
-					armv7,
-				);
 				CLANG_WARN_SUSPICIOUS_IMPLICIT_CONVERSION = YES;
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				GCC_C_LANGUAGE_STANDARD = c99;