diff --git a/src/install.c b/src/install.c
index 2fca8ef..bbc3fe5 100644
--- a/src/install.c
+++ b/src/install.c
@@ -4076,7 +4076,7 @@ static int ppkg_install_package(
     ///                        below is for target                             ///
     //////////////////////////////////////////////////////////////////////////////
 
-    const bool isCrossBuild = (strcmp(sysinfo->type, targetPlatform->name) == 0) && (strcmp(sysinfo->arch, targetPlatform->arch) == 0);
+    const bool isCrossBuild = !((strcmp(sysinfo->type, targetPlatform->name) == 0) && (strcmp(sysinfo->arch, targetPlatform->arch) == 0));
 
     bool isTargetOSFreeBSD = false;
     bool isTargetOSOpenBSD = false;
@@ -4093,12 +4093,13 @@ static int ppkg_install_package(
             isTargetOSNetBSD = true;
             ret = setup_sysroot_for__netbsd(targetPlatform, ppkgHomeDIR, ppkgHomeDIRLength, installOptions->logLevel >= PPKGLogLevel_verbose);
         }
-    }
 
-    if (ret != PPKG_OK) {
-        return ret;
+        if (ret != PPKG_OK) {
+            return ret;
+        }
     }
 
+    printf("isCrossBuild=%d\n",isCrossBuild);
     //////////////////////////////////////////////////////////////////////////////
 
     for (int i = 4; i < 8; i++) {
@@ -4374,8 +4375,8 @@ static int ppkg_install_package(
                 break;
             }
 
-            if (unsetenv(cmakeenvs[i]) != 0) {
-                perror(cmakeenvs[i]);
+            if (unsetenv(name) != 0) {
+                perror(name);
                 return PPKG_ERROR;
             }
         }
@@ -5609,9 +5610,9 @@ int ppkg_setup_toolchain_for_native_build(
     //////////////////////////////////////////////////////////////////////
 
     const KV kvs[3] = {
-        { "PROXIED_NATIVE_CC",   toolchainForNativeBuild->cc   },
-        { "PROXIED_NATIVE_CXX",  toolchainForNativeBuild->cxx  },
-        { "PROXIED_NATIVE_OBJC", toolchainForNativeBuild->objc == NULL ? toolchainForNativeBuild->cc : toolchainForNativeBuild->objc }
+        { "PROXIED_CC_FOR_BUILD",   toolchainForNativeBuild->cc   },
+        { "PROXIED_CXX_FOR_BUILD",  toolchainForNativeBuild->cxx  },
+        { "PROXIED_OBJC_FOR_BUILD", toolchainForNativeBuild->objc == NULL ? toolchainForNativeBuild->cc : toolchainForNativeBuild->objc }
     };
 
     for (int i = 0; i < 3; i++) {
diff --git a/src/ppkg.c b/src/ppkg.c
index cb49183..c8726f6 100644
--- a/src/ppkg.c
+++ b/src/ppkg.c
@@ -222,6 +222,9 @@ int ppkg_main(int argc, char* argv[]) {
         int slashIndex = -1;
 
         for (int i = 0; ;i++) {
+            if (argv[2][i] == '\0') {
+                break;
+            }
             if (argv[2][i] == '/') {
                 slashIndex = i;
                 break;
@@ -598,17 +601,17 @@ int ppkg_main(int argc, char* argv[]) {
                     LOG_ERROR1("--jobs=<N> , <N> should be a non-empty string");
                     return PPKG_ERROR;
                 } else {
-                    int i = 0;
+                    int j = 0;
 
                     for (;;) {
-                        char c = jobsStr[i];
+                        char c = jobsStr[j];
 
                         if (c == '\0') {
                             break;
                         }
 
                         if ((c >= '0') && (c <= '9')) {
-                            i++;
+                            j++;
                         } else {
                             LOG_ERROR1("--jobs=<N> , <N> should be a integer.");
                             return PPKG_ERROR;
@@ -672,9 +675,12 @@ int ppkg_main(int argc, char* argv[]) {
 
             int slashIndex = -1;
 
-            for (int i = 0; ;i++) {
-                if (package[i] == '/') {
-                    slashIndex = i;
+            for (int j = 0; ;j++) {
+                if (package[j] == '\0') {
+                    break;
+                }
+                if (package[j] == '/') {
+                    slashIndex = j;
                     break;
                 }
             }
@@ -906,9 +912,12 @@ int ppkg_main(int argc, char* argv[]) {
 
             int slashIndex = -1;
 
-            for (int i = 0; ;i++) {
-                if (package[i] == '/') {
-                    slashIndex = i;
+            for (int j = 0; ;j++) {
+                if (package[j] == '\0') {
+                    break;
+                }
+                if (package[j] == '/') {
+                    slashIndex = j;
                     break;
                 }
             }
@@ -1135,9 +1144,12 @@ int ppkg_main(int argc, char* argv[]) {
 
             int slashIndex = -1;
 
-            for (int i = 0; ;i++) {
-                if (package[i] == '/') {
-                    slashIndex = i;
+            for (int j = 0; ;j++) {
+                if (package[j] == '\0') {
+                    break;
+                }
+                if (package[j] == '/') {
+                    slashIndex = j;
                     break;
                 }
             }
@@ -1349,9 +1361,12 @@ int ppkg_main(int argc, char* argv[]) {
 
             int slashIndex = -1;
 
-            for (int i = 0; ;i++) {
-                if (package[i] == '/') {
-                    slashIndex = i;
+            for (int j = 0; ;j++) {
+                if (package[j] == '\0') {
+                    break;
+                }
+                if (package[j] == '/') {
+                    slashIndex = j;
                     break;
                 }
             }
@@ -1809,6 +1824,9 @@ int ppkg_main(int argc, char* argv[]) {
         int slashIndex = -1;
 
         for (int i = 0; ;i++) {
+            if (argv[2][i] == '\0') {
+                break;
+            }
             if (argv[2][i] == '/') {
                 slashIndex = i;
                 break;
@@ -1953,6 +1971,9 @@ int ppkg_main(int argc, char* argv[]) {
         int slashIndex = -1;
 
         for (int i = 0; ;i++) {
+            if (argv[2][i] == '\0') {
+                break;
+            }
             if (argv[2][i] == '/') {
                 slashIndex = i;
                 break;
@@ -2316,6 +2337,9 @@ int ppkg_main(int argc, char* argv[]) {
         int slashIndex = -1;
 
         for (int i = 0; ;i++) {
+            if (argv[2][i] == '\0') {
+                break;
+            }
             if (argv[2][i] == '/') {
                 slashIndex = i;
                 break;
@@ -2521,6 +2545,9 @@ int ppkg_main(int argc, char* argv[]) {
         int slashIndex = -1;
 
         for (int i = 0; ;i++) {
+            if (argv[2][i] == '\0') {
+                break;
+            }
             if (argv[2][i] == '/') {
                 slashIndex = i;
                 break;
diff --git a/wrapper-native-c++.c b/wrapper-native-c++.c
index 411d3ba..5133b50 100644
--- a/wrapper-native-c++.c
+++ b/wrapper-native-c++.c
@@ -54,15 +54,15 @@ int main(int argc, char* argv[]) {
 
     /////////////////////////////////////////////////////////////////
 
-    char * const compiler = getenv("CXX_FOR_BUILD");
+    char * const compiler = getenv("PROXIED_CXX_FOR_BUILD");
 
     if (compiler == NULL) {
-        fprintf(stderr, "CXX_FOR_BUILD environment variable is not set.\n");
+        fprintf(stderr, "PROXIED_CXX_FOR_BUILD environment variable is not set.\n");
         return 1;
     }
 
     if (compiler[0] == '\0') {
-        fprintf(stderr, "CXX_FOR_BUILD environment variable value should be a non-empty string.\n");
+        fprintf(stderr, "PROXIED_CXX_FOR_BUILD environment variable value should be a non-empty string.\n");
         return 2;
     }
 
diff --git a/wrapper-native-cc.c b/wrapper-native-cc.c
index 0986363..edfeca1 100644
--- a/wrapper-native-cc.c
+++ b/wrapper-native-cc.c
@@ -54,15 +54,15 @@ int main(int argc, char* argv[]) {
 
     /////////////////////////////////////////////////////////////////
 
-    char * const compiler = getenv("CC_FOR_BUILD");
+    char * const compiler = getenv("PROXIED_CC_FOR_BUILD");
 
     if (compiler == NULL) {
-        fprintf(stderr, "CC_FOR_BUILD environment variable is not set.\n");
+        fprintf(stderr, "PROXIED_CC_FOR_BUILD environment variable is not set.\n");
         return 1;
     }
 
     if (compiler[0] == '\0') {
-        fprintf(stderr, "CC_FOR_BUILD environment variable value should be a non-empty string.\n");
+        fprintf(stderr, "PROXIED_CC_FOR_BUILD environment variable value should be a non-empty string.\n");
         return 2;
     }
 
diff --git a/wrapper-native-objc.c b/wrapper-native-objc.c
index 42ecb4b..899cb69 100644
--- a/wrapper-native-objc.c
+++ b/wrapper-native-objc.c
@@ -54,15 +54,15 @@ int main(int argc, char* argv[]) {
 
     /////////////////////////////////////////////////////////////////
 
-    char * const compiler = getenv("OBJC_FOR_BUILD");
+    char * const compiler = getenv("PROXIED_OBJC_FOR_BUILD");
 
     if (compiler == NULL) {
-        fprintf(stderr, "OBJC_FOR_BUILD environment variable is not set.\n");
+        fprintf(stderr, "PROXIED_OBJC_FOR_BUILD environment variable is not set.\n");
         return 1;
     }
 
     if (compiler[0] == '\0') {
-        fprintf(stderr, "OBJC_FOR_BUILD environment variable value should be a non-empty string.\n");
+        fprintf(stderr, "PROXIED_OBJC_FOR_BUILD environment variable value should be a non-empty string.\n");
         return 2;
     }
 
diff --git a/wrapper-target-clang++.c b/wrapper-target-clang++.c
index cd1f29b..a4a94d8 100644
--- a/wrapper-target-clang++.c
+++ b/wrapper-target-clang++.c
@@ -37,15 +37,15 @@ int main(int argc, char * argv[]) {
 
     /////////////////////////////////////////////////////////////////
 
-    char * const clang = getenv("CXX");
+    char * const clang = getenv("PROXIED_CXX");
 
     if (clang == NULL) {
-        fprintf(stderr, "CXX environment variable is not set.\n");
+        fprintf(stderr, "PROXIED_CXX environment variable is not set.\n");
         return 1;
     }
 
     if (clang[0] == '\0') {
-        fprintf(stderr, "CXX environment variable value should be a non-empty string.\n");
+        fprintf(stderr, "PROXIED_CXX environment variable value should be a non-empty string.\n");
         return 2;
     }
 
diff --git a/wrapper-target-clang.c b/wrapper-target-clang.c
index 1dd12be..f08ace3 100644
--- a/wrapper-target-clang.c
+++ b/wrapper-target-clang.c
@@ -37,15 +37,15 @@ int main(int argc, char * argv[]) {
 
     /////////////////////////////////////////////////////////////////
 
-    char * const clang = getenv("CC");
+    char * const clang = getenv("PROXIED_CC");
 
     if (clang == NULL) {
-        fprintf(stderr, "CC environment variable is not set.\n");
+        fprintf(stderr, "PROXIED_CC environment variable is not set.\n");
         return 1;
     }
 
     if (clang[0] == '\0') {
-        fprintf(stderr, "CC environment variable value should be a non-empty string.\n");
+        fprintf(stderr, "PROXIED_CC environment variable value should be a non-empty string.\n");
         return 2;
     }