From 053f760e2a05ae079059b629d7dcf7c18bbb72e2 Mon Sep 17 00:00:00 2001
From: Tim Snyder <snyder.tim@gmail.com>
Date: Sat, 18 Mar 2023 10:25:27 -0500
Subject: [PATCH] Fix characters from DEFENV literals for conda (#4035) (#4044)

The baked in DEFENV paths might end up with extra NULL characters
at the end if the binaries are installed by something that patches them
for relocatable installs (e.g. conda).  Avoid this issue by immediately
passing them through std::string::c_str() method to stop at the first NULL
---
 src/V3Options.cpp | 35 +++++++++++++++++++++++++----------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/src/V3Options.cpp b/src/V3Options.cpp
index ea3fcf25f..25283e424 100644
--- a/src/V3Options.cpp
+++ b/src/V3Options.cpp
@@ -656,8 +656,11 @@ string V3Options::getenvPERL() {  //
 
 string V3Options::getenvSYSTEMC() {
     string var = V3Os::getenvStr("SYSTEMC", "");
-    if (var == "" && string(DEFENV_SYSTEMC) != "") {
-        var = DEFENV_SYSTEMC;
+    // Treat compiled-in DEFENV string literals as C-strings to enable
+    // binary patching for relocatable installs (e.g. conda)
+    string defenv = string{DEFENV_SYSTEMC}.c_str();
+    if (var == "" && defenv != "") {
+        var = defenv;
         V3Os::setenvStr("SYSTEMC", var, "Hardcoded at build time");
     }
     return var;
@@ -665,8 +668,11 @@ string V3Options::getenvSYSTEMC() {
 
 string V3Options::getenvSYSTEMC_ARCH() {
     string var = V3Os::getenvStr("SYSTEMC_ARCH", "");
-    if (var == "" && string(DEFENV_SYSTEMC_ARCH) != "") {
-        var = DEFENV_SYSTEMC_ARCH;
+    // Treat compiled-in DEFENV string literals as C-strings to enable
+    // binary patching for relocatable installs (e.g. conda)
+    string defenv = string{DEFENV_SYSTEMC_ARCH}.c_str();
+    if (var == "" && defenv != "") {
+        var = defenv;
         V3Os::setenvStr("SYSTEMC_ARCH", var, "Hardcoded at build time");
     }
     if (var == "") {
@@ -697,8 +703,11 @@ string V3Options::getenvSYSTEMC_ARCH() {
 
 string V3Options::getenvSYSTEMC_INCLUDE() {
     string var = V3Os::getenvStr("SYSTEMC_INCLUDE", "");
-    if (var == "" && string(DEFENV_SYSTEMC_INCLUDE) != "") {
-        var = DEFENV_SYSTEMC_INCLUDE;
+    // Treat compiled-in DEFENV string literals as C-strings to enable
+    // binary patching for relocatable installs (e.g. conda)
+    string defenv = string{DEFENV_SYSTEMC_INCLUDE}.c_str();
+    if (var == "" && defenv != "") {
+        var = defenv;
         V3Os::setenvStr("SYSTEMC_INCLUDE", var, "Hardcoded at build time");
     }
     if (var == "") {
@@ -710,8 +719,11 @@ string V3Options::getenvSYSTEMC_INCLUDE() {
 
 string V3Options::getenvSYSTEMC_LIBDIR() {
     string var = V3Os::getenvStr("SYSTEMC_LIBDIR", "");
-    if (var == "" && string(DEFENV_SYSTEMC_LIBDIR) != "") {
-        var = DEFENV_SYSTEMC_LIBDIR;
+    // Treat compiled-in DEFENV string literals as C-strings to enable
+    // binary patching for relocatable installs (e.g. conda)
+    string defenv = string{DEFENV_SYSTEMC_LIBDIR}.c_str();
+    if (var == "" && defenv != "") {
+        var = defenv;
         V3Os::setenvStr("SYSTEMC_LIBDIR", var, "Hardcoded at build time");
     }
     if (var == "") {
@@ -724,8 +736,11 @@ string V3Options::getenvSYSTEMC_LIBDIR() {
 
 string V3Options::getenvVERILATOR_ROOT() {
     string var = V3Os::getenvStr("VERILATOR_ROOT", "");
-    if (var == "" && string(DEFENV_VERILATOR_ROOT) != "") {
-        var = DEFENV_VERILATOR_ROOT;
+    // Treat compiled-in DEFENV string literals as C-strings to enable
+    // binary patching for relocatable installs (e.g. conda)
+    string defenv = string{DEFENV_VERILATOR_ROOT}.c_str();
+    if (var == "" && defenv != "") {
+        var = defenv;
         V3Os::setenvStr("VERILATOR_ROOT", var, "Hardcoded at build time");
     }
     if (var == "") v3fatal("$VERILATOR_ROOT needs to be in environment\n");