diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index 06c00a5..c78f8ae 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -6,3 +6,4 @@
 * [Shang Yuanchun](https://github.com/ideal)
 * [Shreyas Balakrishna](https://github.com/shreyasbharath)
 * [Jim Keener](https://github.com/jimktrains)
+* [Dean T](https://github.com/deanoburrito)
diff --git a/nanoprintf.h b/nanoprintf.h
index 081fc47..8273764 100644
--- a/nanoprintf.h
+++ b/nanoprintf.h
@@ -744,7 +744,7 @@ int npf_vpprintf(npf_putc pc, void *pc_ctx, char const *format, va_list args) {
         cbuf = va_arg(args, char *);
 #if NANOPRINTF_USE_PRECISION_FORMAT_SPECIFIERS == 1
         for (char const *s = cbuf;
-             *s && ((fs.prec_opt == NPF_FMT_SPEC_OPT_NONE) || (cbuf_len < fs.prec));
+             ((fs.prec_opt == NPF_FMT_SPEC_OPT_NONE) || (cbuf_len < fs.prec)) && *s;
              ++s, ++cbuf_len);
 #else
         for (char const *s = cbuf; *s; ++s, ++cbuf_len); // strlen
diff --git a/tests/unit_vpprintf.cc b/tests/unit_vpprintf.cc
index 05cbcd1..ac029ec 100644
--- a/tests/unit_vpprintf.cc
+++ b/tests/unit_vpprintf.cc
@@ -10,6 +10,8 @@
   #if NANOPRINTF_CLANG
     #pragma GCC diagnostic ignored "-Wformat-pedantic"
     #pragma GCC diagnostic ignored "-Wold-style-cast"
+  #else
+    #pragma GCC diagnostic ignored "-Wformat-overflow"
   #endif
   #pragma GCC diagnostic ignored "-Wformat"
   #pragma GCC diagnostic ignored "-Wformat-zero-length"
@@ -78,6 +80,11 @@ TEST_CASE("npf_vpprintf") {
     REQUIRE(r.String() == std::string{"abcdefgh"});
   }
 
+  SUBCASE("string precision zero null pointer") {
+    REQUIRE(npf_pprintf(r.PutC, &r, "%.0s", nullptr) == 0);
+    REQUIRE(r.String() == std::string{""});
+  }
+
   SUBCASE("signed int zero") {
     REQUIRE(npf_pprintf(r.PutC, &r, "%i", 0) == 1);
     REQUIRE(r.String() == std::string{"0"});