Build ImHex for macOS

readme.txt

It is a pretty dirty hack, but it works.

In the attached diff:
- fixed type mismatch for min/max
- replaced ftello64/fseeko64
- disabled llvm::demangle to fix link error due to llvm lib mismatch on my machine

First exported GCC 10.2 before CMake
export CC=/usr/local/bin/gcc-10
export CXX=/usr/local/bin/g++-10

Then just built with frameworks and lib paths (proper way would be to fix CMakeLists.txt :P )
-L/usr/local/lib/ 
-L/usr/local/Cellar/openssl@1.1/1.1.1h/lib/ 
-L/usr/local/Cellar/llvm/11.0.0/lib/ 
-framework Foundation 
-framework Cocoa 
-framework IOKit 

ImHex.diff

diff --git a/source/helpers/crypto.cpp b/source/helpers/crypto.cpp
index fa23428..e0ef3ad 100644
--- a/source/helpers/crypto.cpp
+++ b/source/helpers/crypto.cpp
@@ -41,7 +41,7 @@ namespace hex {
         std::array<u8, 512> buffer = { 0 };
 
         for (u64 bufferOffset = 0; offset < size; offset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
 
             for (size_t i = 0; i < readSize; i++) {
@@ -74,7 +74,7 @@ namespace hex {
         std::array<u8, 512> buffer = { 0 };
 
         for (u64 bufferOffset = 0; offset < size; offset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
 
             for (size_t i = 0; i < readSize; i++) {
@@ -94,7 +94,7 @@ namespace hex {
 
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             MD4_Update(&ctx, buffer.data(), readSize);
         }
@@ -113,7 +113,7 @@ namespace hex {
 
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             MD5_Update(&ctx, buffer.data(), readSize);
         }
@@ -131,7 +131,7 @@ namespace hex {
         SHA1_Init(&ctx);
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             SHA1_Update(&ctx, buffer.data(), readSize);
         }
@@ -150,7 +150,7 @@ namespace hex {
 
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             SHA224_Update(&ctx, buffer.data(), readSize);
         }
@@ -169,7 +169,7 @@ namespace hex {
 
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             SHA256_Update(&ctx, buffer.data(), readSize);
         }
@@ -188,7 +188,7 @@ namespace hex {
 
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             SHA384_Update(&ctx, buffer.data(), readSize);
         }
@@ -207,7 +207,7 @@ namespace hex {
 
         std::array<u8, 512> buffer = { 0 };
         for (u64 bufferOffset = 0; bufferOffset < size; bufferOffset += buffer.size()) {
-            const u64 readSize = std::min(buffer.size(), size - bufferOffset);
+            const u64 readSize = std::min((u64)buffer.size(), size - bufferOffset);
             data->read(offset + bufferOffset, buffer.data(), readSize);
             SHA512_Update(&ctx, buffer.data(), readSize);
         }
diff --git a/source/lang/evaluator.cpp b/source/lang/evaluator.cpp
index f5241c6..b1fab50 100644
--- a/source/lang/evaluator.cpp
+++ b/source/lang/evaluator.cpp
@@ -179,7 +179,7 @@ namespace hex::lang {
             }
             else {
                 members.push_back(pattern);
-                unionSize = std::max(memberSize, unionSize);
+                unionSize = std::max(memberSize, (u64)unionSize);
             }
         }
 
diff --git a/source/providers/file_provider.cpp b/source/providers/file_provider.cpp
index a6deb2a..73503d5 100644
--- a/source/providers/file_provider.cpp
+++ b/source/providers/file_provider.cpp
@@ -51,7 +51,7 @@ namespace hex::prv {
         if ((offset + size) > this->getSize() || buffer == nullptr || size == 0)
             return;
 
-        fseeko64(this->m_file, this->getCurrentPage() * PageSize + offset, SEEK_SET);
+        fseeko(this->m_file, this->getCurrentPage() * PageSize + offset, SEEK_SET);
         size_t readSize = fread(buffer, 1, size, this->m_file);
 
 
@@ -75,7 +75,7 @@ namespace hex::prv {
         if ((offset + size) > this->getSize() || buffer == nullptr || size == 0)
             return;
 
-        fseeko64(this->m_file, this->getCurrentPage() * PageSize + offset, SEEK_SET);
+        fseeko(this->m_file, this->getCurrentPage() * PageSize + offset, SEEK_SET);
         fread(buffer, 1, size, this->m_file);
     }
 
@@ -83,12 +83,12 @@ namespace hex::prv {
         if (buffer == nullptr || size == 0)
             return;
 
-        fseeko64(this->m_file, offset, SEEK_SET);
+        fseeko(this->m_file, offset, SEEK_SET);
         fwrite(buffer, 1, size, this->m_file);
     }
     size_t FileProvider::getActualSize() {
-        fseeko64(this->m_file, 0, SEEK_END);
-        return ftello64(this->m_file);
+        fseeko(this->m_file, 0, SEEK_END);
+        return ftello(this->m_file);
     }
 
     std::vector<std::pair<std::string, std::string>> FileProvider::getDataInformation() {
diff --git a/source/views/view_data_inspector.cpp b/source/views/view_data_inspector.cpp
index 4f23f8b..2c3c293 100644
--- a/source/views/view_data_inspector.cpp
+++ b/source/views/view_data_inspector.cpp
@@ -13,7 +13,7 @@ namespace hex {
         View::subscribeEvent(Events::RegionSelected, [this](const void* userData){
             Region region = *static_cast<const Region*>(userData);
 
-            this->m_validBytes = std::min(this->m_dataProvider->getSize() - region.address, sizeof(PreviewData));
+            this->m_validBytes = std::min(sizeof(this->m_dataProvider->getSize() - region.address), sizeof(PreviewData));
             std::memset(&this->m_previewData, 0x00, sizeof(PreviewData));
             this->m_dataProvider->read(region.address, &this->m_previewData, sizeof(PreviewData));
 
diff --git a/source/views/view_hexeditor.cpp b/source/views/view_hexeditor.cpp
index cc4f7e8..bc985b8 100644
--- a/source/views/view_hexeditor.cpp
+++ b/source/views/view_hexeditor.cpp
@@ -490,7 +490,7 @@ namespace hex {
             return false;
 
         fseek(file, 0, SEEK_END);
-        size_t size = ftello64(file);
+        size_t size = ftello(file);
         rewind(file);
 
         data.resize(size);
@@ -746,7 +746,7 @@ R"(
         std::vector<u8> buffer(1024, 0x00);
         size_t dataSize = provider->getSize();
         for (u64 offset = 0; offset < dataSize; offset += 1024) {
-            size_t usedBufferSize = std::min(buffer.size(), dataSize - offset);
+            size_t usedBufferSize = std::min((u64)buffer.size(), dataSize - offset);
             provider->read(offset, buffer.data(), usedBufferSize);
 
             for (u64 i = 0; i < usedBufferSize; i++) {
@@ -784,7 +784,7 @@ R"(
         std::vector<u8> buffer(1024, 0x00);
         size_t dataSize = provider->getSize();
         for (u64 offset = 0; offset < dataSize; offset += 1024) {
-            size_t usedBufferSize = std::min(buffer.size(), dataSize - offset);
+            size_t usedBufferSize = std::min((u64)buffer.size(), dataSize - offset);
             provider->read(offset, buffer.data(), usedBufferSize);
 
             for (u64 i = 0; i < usedBufferSize; i++) {
diff --git a/source/views/view_information.cpp b/source/views/view_information.cpp
index 0386b2e..bf9439d 100644
--- a/source/views/view_information.cpp
+++ b/source/views/view_information.cpp
@@ -63,7 +63,7 @@ namespace hex {
 
                         for (u64 i = 0; i < this->m_dataProvider->getSize(); i += this->m_blockSize) {
                             std::array<float, 256> blockValueCounts = { 0 };
-                            this->m_dataProvider->read(i, buffer.data(), std::min(size_t(this->m_blockSize), this->m_dataProvider->getSize() - i));
+                            this->m_dataProvider->read(i, buffer.data(), std::min(u64(this->m_blockSize), this->m_dataProvider->getSize() - i));
 
                             for (size_t j = 0; j < this->m_blockSize; j++) {
                                 blockValueCounts[buffer[j]]++;
diff --git a/source/views/view_strings.cpp b/source/views/view_strings.cpp
index 0e09cfc..e5a25da 100644
--- a/source/views/view_strings.cpp
+++ b/source/views/view_strings.cpp
@@ -37,7 +37,8 @@ namespace hex {
             }
             ImGui::Separator();
             if (ImGui::MenuItem("Demangle")) {
-                this->m_demangledName = llvm::demangle(this->m_selectedString);
+                //this->m_demangledName = llvm::demangle(this->m_selectedString);
+                this->m_demangledName = this->m_selectedString;
                 if (!this->m_demangledName.empty())
                     View::doLater([]{ ImGui::OpenPopup("Demangled Name"); });
             }
@@ -55,7 +56,7 @@ namespace hex {
             std::vector<u8> buffer(1024, 0x00);
             u32 foundCharacters = 0;
             for (u64 offset = 0; offset < this->m_dataProvider->getSize(); offset += buffer.size()) {
-                size_t readSize = std::min(buffer.size(), this->m_dataProvider->getSize() - offset);
+                size_t readSize = std::min((u64)buffer.size(), this->m_dataProvider->getSize() - offset);
                 this->m_dataProvider->read(offset,  buffer.data(), readSize);
 
                 for (u32 i = 0; i < readSize; i++) {
diff --git a/source/views/view_tools.cpp b/source/views/view_tools.cpp
index a0d4c0d..dcde3cb 100644
--- a/source/views/view_tools.cpp
+++ b/source/views/view_tools.cpp
@@ -76,7 +76,7 @@ namespace hex {
     void ViewTools::drawDemangler() {
         if (ImGui::CollapsingHeader("Itanium/MSVC demangler")) {
             if (ImGui::InputText("Mangled name", this->m_mangledBuffer, 0xF'FFFF)) {
-                this->m_demangledName = llvm::demangle(this->m_mangledBuffer);
+                //this->m_demangledName = llvm::demangle(this->m_mangledBuffer);
             }
 
             ImGui::InputText("Demangled name", this->m_demangledName.data(), this->m_demangledName.size(), ImGuiInputTextFlags_ReadOnly);

It looks like the patch was recently merged: WerWolv/ImHex@4720cf9

Hehe, sweeeeeeet!
I wish someone make changes to CMakeLists as well :D